Active components and photosensitive resin composition containing the same

ABSTRACT

A photosensitive resin composition for using in combination with a photosensitizer comprises an active component selected from an active metal alkoxide represented by the formula (1) or a polycondensate thereof and a particle represented by the formula (2),
 
(X) m-n -M m -[(U 1 ) p —(U 2 -Z) t ] n   (1)
 
P—[(Y) s —{(U 1)   p —(U 2 -Z) t }] k   (2)
         wherein, X shows a hydrogen, a halogen, an alkoxy group or an alkoxycarbonyl group, M shows a metal atom whose valence m is not less than 2, U 1  shows a first connecting unit, U 2  shows a second connecting unit and Z shows a group causing a difference in solubility by light exposure, P shows a fine particle carrier, Y shows a coupling residue, n shows an integer of not less than 1 and m&gt;n, p shows 0 or 1, t shows 1 or 2, k shows an integer of not less than 1, and s shows 0 or 1).       

     The unit (U 1 )p—(U 2 -Z)t is represented by the following formula:
 
f(R1)q-(B)r]p-({(R2),,-(Ar)v}-Zlt
         (wherein, R1 and R2 show an alkylene or alkenylene group; and B shows an ester bond, an amide bond, a urea bond, a urethane bond, an imino group, a sulfur atom or a nitrogen atom; Ar represents an arylene or cycloalkylene group; each of the factors, q, r, a and v, shows 0 or 1, and q+r+u+vzl; and Z, p and t have the same meanings defined above).

This application is the National Phase of International ApplicationPCT/JP01/10571 filed Dec. 4, 2001 which designated the U.S. and thatInternational Application was not published under PCT Article 21(2) inEnglish.

TECHNICAL FIELD

The present invention relates to an active component which is useful forforming minute patterns such as semiconductor integrated circuits usinga beam, for example, ultraviolet rays or far-ultraviolet rays (includingexcimer lasers or the like); a photosensitive resin composition (resistcomposition) using the same; and a process for forming a pattern usingthe same.

BACKGROUND ART

In the field of semiconductor resists, with developing very large scaleintegrated circuits, higher minute processing techniques have beendemanded. Thereupon, light sources of shorter wavelength such as KrFexcimer laser (wavelength: 248 nm), ArF excimer laser (wavelength: 193nm) and F2 excimer laser (wavelength: 157 nm) are utilized instead ofg-ray (wavelength: 436 mm) or i-ray (wavelength: 365 mm) of aconventional high-pressure mercury lamp.

However, even when KrF excimer laser or ArF excimer laser is applied toa conventional resist material such as a novolakresin/diazonaphthoquinone-based positive resist, in which g-ray or i-rayis used, sensitivity and resolution of the conventional resist materialsare considerably deteriorated owing to light absorption by the novolakresin.

Moreover, with rises in the integration level and performance ofsemiconductor integrated circuits, there has been demand for resistswith better resolution (patterns in submicron order, quartermicron orderor smaller) and for improvement of etching resistance in the process ofdry development.

For example, as an approach for improving resolution with the use ofconventional process for dry development, there has been known a methodin which a photosensitive resin is filled with inorganic fine particles,and silicasol and the like are utilized as the inorganic fine particleto impart both resist performance (sensitivity, resolution, etc.) anddry etching resistance. To illustrate, in order to improve dry etchingresistance, Japanese Patent Application Laid-Open No. 158235/1993(JP-5-158235A) discloses a resist composition comprising a resistcomposed of a cresol novolak resin and naphthoquinonediazido sulfonicester, in which silicasol added to the resist, and the resistcomposition is used as an upper layer resist of bilayer. Japanese PatentApplication Laid-Open No. 194491/1999 (JP-11-194491A) proposes aphotosensitive resin composition, which comprises a photosensitiveorganic oligomer or polymer, a hydrolyzable and polymerizable organicmetal compound or its condensate, and an inorganic filler having afunctional group (e.g., silicasol). Japanese Patent ApplicationLaid-Open No. 327125/1999 (JP-11-327125A) discloses a photosensitiveresin composition comprising a photosensitive resin, an inorganic fineparticle (e.g., silicasol) or an inorganic fine particle having afunctional group. Sondi and Matijevic disclose a film composed of ap-hydroxystyrene-t-butyl acrylate copolymer containing SiO₂nanoparticles (silicasol), and report that the SiO₂ nanoparticle ishighly soluble in a base to act as a solution accelerator and that theresist including such a SiO₂ nanoparticle shows almost the sameresolution with control (resist) not comprising SiO₂ (I. Sondi and E.Matijevic, Resist Technology and Processing XVII, Francis M. Houlihan,Editor, Proceedings of SPIE Vol. 3999(2000), pp. 627-637). Moreover,this literature discloses that a resist system using a transparent SiO₂nanoparticle is useful to wavelengths such as 157 nm.

On the other hand, with the improvement of miniaturization, recently,edge roughness of resist patterns has been becoming of a problem inparticular. The edge roughness is particularly prominent in the resistused in thin films such as surface layer resists.

In the above-mentioned resist comprising a silicasol added thereto, afilm can be thickened because the silicasol is small in a particle sizeand is transparent to exposure beam. Further, owing to the small size ofsilicasol particle, thin film is also obtainable and resolution thereofcan be improved to a certain degree. However, since the resist isdissolved at the area where the resist is inhibited from dissolution(e.g., non-exposed area in the case of positive resist) due to highhydrophilicity of silicasol itself, difference in dissolution ratebetween exposed area and non-exposed area cannot be increased (enlarged)in the above-mentioned resist, therefore resolution, and sharpness oredge roughness of pattern profile cannot be greatly improved.

Moreover, a commercially available silicasol is mostly manufactured bysodium silicate method, therefore sodium may be inevitably left in theproducts.

Japanese Patent Application Laid-Open No. 56463/2000 (JP-2000-56463A)discloses that an alcohol solution of a resist material containing analkali-soluble resin is added with an organooxysilane, and subjected toa sol-gel reaction in the presence of moisture to give a silica-alkalisoluble resin hybrid material. In this method, a silica component can beuniformly dispersed in the resist material on molecular level with thesilica components prevented from precipitation, by conducting a sol-gelreaction in the resist. However, great improvement of resist performancesuch as resolution is hardly achieved by this method because thedifference in solubility between exposed area and non-exposed area in adeveloper cannot be enlarged.

Moreover, as a resist composition, there has been known alight-amplifying (chemical-amplifying) resist composition comprising abase resin which becomes alkali-soluble with leaving (removing) by anaction of an acid, in combination with a photoactive acid generator.However, the difference in solubility between exposed area andnon-exposed area cannot be increased even in this composition.

Accordingly, it is an object of the present invention to provide anactive component (including an active particle), that is useful forforming a pattern with high sensitivity and high resolution; aphotosensitive resin composition comprising the active component; and aprocess for forming a pattern using the photosensitive resincomposition.

It is another object of the present invention to provide aphotosensitive resin composition which improves edge roughness of thepattern with etching resistance against oxygen plasma kept; and aprocess for forming a pattern.

It is still another object of the present invention to provide aphotosensitive resin composition which is efficient for largelyimproving resolution with high sensitivity to shorter wavelength beams(rays); and a process for forming a pattern using the same.

It is other object of the present invention to provide an activecomponent (including an active particle) useful for forming a patternwith high sensitivity and high resolution in which contamination ofimpurities is inhibited (avoided); an active metal alkoxide useful forproviding the active component; a photosensitive resin compositioncomprising the active component; and a process for forming a patternusing the photosensitive resin composition.

It is still other object of the present invention to provide aphotosensitive resin composition and a process for forming a patternusing the same, which can cause (make) a difference in solubilitybetween exposed area and non-exposed area in a developer.

DISCLOSURE OF INVENTION

The inventors of the present invention made intensive and extensivestudies to achieve the above-mentioned objects and finally found thatthe combination use of an active component and a photosensitive resincomposition is attributed to forming high resolution pattern with highsensitivity because of a difference in solubility in a developer betweenexposed area and non-exposed area, wherein a functional group isintroduced into the active component [e.g., a fine or finely dividedparticle (an active particle) capable of being hydrophilic byeliminating a hydrophobic leaving group owing to at least lightexposure, a specific metal alkoxide (an active metal alkoxide) or thepolycondensate thereof (an active particle formed by polycondensation)]to cause (yield) a difference in solubility owing to light exposure, andthat the combination use of the metal alkoxide or a polycondensatethereof, and a photosensitive resin composition, is attributed toforming high(er) resolution pattern with higher sensitivity because ofreduction of impurity incorporation. The present invention wasaccomplished based on the above findings.

That is, the active component (constituent) of the present invention isthe one for using (the one which is used or usable) in combination witha photosensitizer which constitutes a photosensitive resin composition,wherein the component comprises at least one member selected from thegroup consisting of an active metal alkoxide represented by thefollowing formula (1):(X)_(m-n)-M^(m)-[(U₁)_(p)—(U₂-Z)_(t)]_(n)  (1)

(wherein, X represents a hydrogen atom, a halogen atom, an alkoxy groupor an alkoxycarbonyl group, M represents a metal atom whose valence m isnot less than 2, U₁ represents a first connecting unit, U₂ represents asecond connecting unit, Z represents a group causing (making) adifference in solubility by (through or owing to) light exposure, nrepresents an integer of not less than 1 and m>n, p represents 0 or 1,and t represents an integer of not less than 1 (e.g., 1 or 2)), or apolycondensate thereof, and a particle (particulate) represented by thefollowing formula (2):P—[(Y)_(s)-{(U₁)_(p)—(U₂-Z)_(t)}]_(k)  (2)

(wherein, P represents a fine (minute) particle carrier, Y represents acoupling residue, k represents an integer of not less than 1, srepresents 0 or 1, and U₁, U₂, Z, p and t have the same meanings definedabove). Incidentally, the first connecting unit U₁ and the secondconnecting unit U₂ are generically referred to as connecting unit U insome cases. The particle (active particle) represented by the formula(2) may be a reaction product of an active metal alkoxide represented bythe formula (1) or a polycondensate thereof, with a fine particlecarrier P.

The active component may be in the form (morphology or configuration) ofa particle or an oligomer, and the group Z may be (a) aphoto-crosslinkable group or a photo-curable group, or (b) a hydrophilicgroup protected by a protective group which is capable (competent orqualified) of removing (removable) by (owing to) light exposure. Thegroup Z may be usually a hydrophilic group protected by a protectivegroup which is capable of removing (removable) by light exposure inassociation with a photosensitizer, and the protective group is capableof removing (removable) by an action of an acid and others. The group Zis capable (competent or qualified) of forming (formable or form-able) ahydroxyl group or a carboxyl group by removal (elimination) of ahydrophobic protective group, and such a group Z is represented, forexample, by a group -HP-Pro (wherein, HP represents a hydrophilic groupand Pro represents a protective group which imparts hydrophobicity tothe hydrophilic group HP and forms the hydrophilic group HP by removing(leaving) owing to light exposure).

The protective group may be (i) a protective group for a hydroxyl group,selected from the group consisting of an alkoxyalkyl group, an acylgroup, an alkoxycarbonyl group, an oxacycloalkyl group and a crosslinkedcyclic alicyclic group; or (ii) a protective group for a carboxyl group,selected from the group consisting of an alkyl group, a carbamoyl groupand a crosslinked cyclic alicyclic group. Specifically, the protectivegroup may be (1) a protective group for a hydroxyl group, selected fromthe group consisting of a C₁₋₆alkyl-carbonyl group, aC₁₋₆alkoxy-C₁₋₆alkyl group, a C₁₋₆alkoxy-carbonyl group and anoxacycloalkyl group; or (2) a protective group for a carboxyl group,selected from the group consisting of a C₁₋₆alkyl group, a carbamoylgroup, a C₁₋₆alkyl-carbamoyl group, a C₆₋₁₀aryl-carbamoyl group and abi- or tricycloalkyl group.

The metal atom M may be aluminium, titanium, zirconium or silicon, isusually silicon.

The connecting units U₁ and U₂ may comprise various connecting group,for example, may comprise a unit containing at least one member selectedfrom the group consisting of a chain hydrocarbon, a hydrocarbon ring, achain hydrocarbon having a hetero atom, and a heterocycle. For example,the connecting units U₁ and U₂ may be respectively represented by thefollowing formulae:—(R¹)_(q)—(B)_(r)—, —(R²)_(u)—(Ar)_(v)—

(wherein, each of the factors, R¹ and R², is either same or different,representing an alkylene group or an alkenylene group, B represents anester bond, a thioester bond, an amide bond, a urea bond, a urethanebond, a thiourethane bond, an imino group, a sulfur atom or a nitrogenatom, Ar represents an arylene or cycloalkylene group which may have asubstituent (e.g., a halogen atom and an alkyl group), each of thefactors, q, r, u and v, represents 0 or 1, and q+r+u+v≧1).

The compound represented by the formula (1) may be a one in which thegroup Z means a hydroxyl or carboxyl group protected by a hydrophobicprotective group which is capable of removing (removable) by (owing to)light exposure, the metal atom M is selected from group consisting ofaluminium, titanium, zirconium and silicon, and the unit(U₁)_(p)—(U₂-Z)_(t) containing a connecting unit is represented by thefollowing formula:[(R¹)_(q)—(B)_(r)]_(p)—[{(R²)_(u)—(Ar)_(v)}-Z]_(t)

(wherein, R¹, R², B, Ar, p, q, r, t, u and v have the same meaningsdefined above).

Further, the polycondensate of the active metal alkoxide (1) may be apolycondensate of the active metal alkoxide represented by the formula(1) alone (singly) or a polycondensate (copolycondensate) of the activemetal alkoxide represented by the formula (1) and a metal alkoxiderepresented by the following formula (5):(X)_(m-n-1)M^(m)(R⁵)_(n-1)  (5)

(wherein, R⁵ represents a hydrogen atom or an alkyl group, X, M, m and nhave the same meanings defined above).

The weight ratio of the active metal alkoxide (1) relative to the metalalkoxide (5) may be, for example, about 10/90 to 90/10. Thepolycondensate may be in the form of a particle (particulate), forexample, a particle having a mean particle size of about 1 to 100 nm.

In the particle (active particle) represented by the formula (2), themean particle size of the fine particle carrier may be about 1 to 100nm. The fine particle carrier may be an organic fine particle carrier oran inorganic fine particle carrier (e.g., silicasol). Incidentally, acoupling agent associates with a compound having the metal atom M of theformula (1). Such an active particle (2) may comprise a connecting unitU connecting with an inorganic fine particle P whose mean particle sizeis 1 to 50 nm through (via) a silane coupling agent Y, a hydrophilicgroup connecting with the connecting unit, and a protective group whichprotects the hydrophilic group. Moreover, the group Z which causes(makes) a difference in solubility by (through) light exposure maycomprise the hydrophilic group and the protective group. The connectingunit may comprise at least one member selected from the group consistingan aromatic C₆₋₁₂hydrocarbon ring, a monocyclic alicyclic hydrocarbonring, a crosslinked cyclic alicyclic hydrocarbon ring and an aliphatichydrocarbon chain, and the hydrophilic group is usually a hydroxyl groupor a carboxyl group. The protective group may be (1) a protective groupfor the hydroxyl group, selected from the group consisting of aC₁₋₄alkyl-carbonyl group, a C₁₋₄alkoxy-C₁₋₄alkyl group, aC₁₋₄alkoxy-carbonyl group and a 5- or 6-membered oxacycloalkyl group, or(2) a protective group for the carboxyl group, selected from the groupconsisting of a C₁₋₄alkyl group, a carbamoyl group, aC₁₋₄alkyl-carbamoyl group, a C₆₋₁₀aryl-carbamoyl group and a bi- ortricycloalkyl group. The amount of the silane coupling agent may beabout 0.1 to 200 parts by weight relative to 100 parts by weight of thefine particle carrier.

The present invention includes a photosensitive resin compositioncontaining the active component, for example includes a photosensitiveresin composition which comprises a base resin, a photosensitizer andthe active component. The photosensitive resin composition may be apositive one in which an exposed area is water- or alkali-soluble. Forexample, the photosensitive resin composition may be a one in which abase resin comprises a homo- or copolymer of a monomer which is capableof forming (formable) a hydrophilic group by an action of an acid, and aphotosensitizer comprises an photoactive acid generator. In order toform a pattern, such a photosensitive composition may be applied orcoated onto a substrate, the coating layer may be exposed to light, thelight-exposed layer may be heat-treated, and the heat-treated layer maybe developed.

The present invention includes an active metal alkoxide which isrepresented by the following formula (1):(X)_(m-n)-M^(m)-{(U₁)_(p)—(U₂-Z)_(t)}_(n)  (1)

(wherein, X represents a hydrogen atom, a halogen atom, an alkoxy groupor an alkoxycarbonyl group, M represents a metal atom whose valence m isnot less than 2, U₁ represents a first connecting unit, U₂ represents asecond connecting unit, Z represents a group causing a difference insolubility by light exposure, n represents an integer of not less than 1and m>n, p represents 0 or 1, and t represents 1 or 2).

Furthermore, the present invention includes an oligomer or an activeparticle, which comprises at least a polycondensate of the active metalalkoxide.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows ¹H-NMR spectrum of a compound obtained in the step (2) (ii)in Example 1.

FIG. 2 shows IR spectrum of the compound obtained in the step (2) (ii)in Example 1.

FIG. 3 shows ¹H-NMR spectrum of a compound obtained in the step (2) (i)in Example 3.

FIG. 4 shows IR spectrum of the compound obtained in the step (2) (i) inExample 3.

FIG. 5 shows ¹H-NMR spectrum of a compound obtained in the step (2) (ii)in Example 17.

FIG. 6 shows ¹H-NMR spectrum of a compound obtained in the step (2)(iii) in Example 21.

BEST MODE FOR CARRYING OUT OF THE INVENTION

The active component (or ingredient) of the present invention is used(or usable) in combination with a photosensitizer which constitutes aphotosensitive resin composition, and has a unit for causing adifference in solubility owing to at least light exposure. Such anactive component comprises at least one member selected from the groupconsisting of the active metal alkoxide represented by the formula (1)or the polycondensate thereof, and the particle represented by theformula (2).

[Active Metal Alkoxide or a Polycondensate thereof (1)]

(Active Metal Alkoxide (1a))

In the formula (1), the halogen atom represented by X includes fluorine,chlorine, bromine and iodine atoms. As the alkoxy group, there may beexemplified a linear or branched chain C₁₋₁₀alkoxy group such as amethoxy, ethoxy, propoxy, isopropoxy, butoxy, s-butoxy, t-butoxy,pentyloxy, hexyloxy, heptyloxy, octyloxy and decyloxy group (preferablya C₁₋₆alkoxy group, more preferably a C₁₋₄alkoxy group). As thealkoxycarbonyl group, there may be exemplified a linear or branchedchain C₁₋₁₀alkoxy-carbonyl group such as a methoxycarbonyl,ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl,s-butoxycarbonyl, t-butoxycarbonyl, hexyloxycarbonyl andoctyloxycarbonyl group (preferably a C₁₋₆alkoxy-carbonyl group, morepreferably a C₁₋₄alkoxy-carbonyl group).

The alkoxy group or alkoxycarbonyl group may have a substituent such asa halogen atom, a hydrocarbon group which may have an unsaturated bond(an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group,etc.), a heterocyclic group and an acyl group.

The metal atom whose valence is m, represented by M, is a metal whosevalence is not less than 2 (e.g., bivalent to quadrivalent) and which iscapable of forming a metal alkoxide, for example, an alkaline earthmetal (magnesium, calcium, etc.), a transition metal, a rare earth metalor a metal element of the Groups 3 to 5 and 13 to 15 of the PeriodicTable of Elements. In particular, there may be mentioned a metal elementof the Group 3 (such as yttrium), a metal element of the Group 4 (suchas titanium and zirconium), a metal element of the Group 13 (such asaluminium), a metal element of the Group 14 (such as silicon), and thelike. Preferred metal is titanium, zirconium, aluminium and silicon,especially silicon.

As the group Z, a group causing a difference in solubility by lightexposure may be mentioned, for example, (a) a photo-crosslinkable groupor a photo-curable group, or (b) a hydrophilic group protected by aprotective group.

As the (a) photo-crosslinkable or photo-curable group, there may beexemplified azide group, cinnamoyl group, cinnamylidene group, apolymerizable group (a (meth)acryloyl group, allyl group, vinyl group,etc.) and the like. The polymerizable group and the crosslinkable groupare especially preferred.

As the hydrophilic group of the (b) hydrophilic group protected by aprotective group, there may be mentioned, a water- or alkali-solublegroup (a group which imparts solubility by an action of water or analkali), for example, in addition to an amino group and an N-substitutedamino group (e.g., an N,N-diC₁₋₄alkylamino group) and the like, ahydroxyl group, a carboxyl group and a sulfur-containing derivativegroup corresponding to the above-mentioned groups (including a mercaptogroup, a thiocarboxyl group, a dithiocarboxyl group). The hydroxyl group(including a phenolic hydroxyl group) and the carboxyl group areespecially preferable.

In the formula (1), n represents an integer of not less than 1 (e.g., 1to 3, especially 1 or 2). Incidentally, m is larger than n (m>n), and mminus n leaves 1 to 3 (m-n=1-3), preferably 2 or 3.

A first connecting unit U₁ and a second connecting unit U₂ are notparticularly restricted, and comprise an unit of various organic chains(e.g., a chain hydrocarbon, a hydrocarbon ring, a chain hydrocarbonhaving a hetero atom and a heterocycle) singly or in combination, andthese organic chains may be connected through a connecting (or binding)group. The chain hydrocarbon includes an aliphatic hydrocarbon chainsuch as alkylene chain (e.g., a linear or branched C₁₋₁₀alkylene chainsuch as an ethylene chain, a propylene chain, a trimethylene chain and ahexamethylene chain; a linear or branched C₂₋₁₀alkenylene chain such asa vinylene chain, a propenylene chain, a isopropenylene chain and abutenylene chain; and the like). The chain hydrocarbon having a heteroatom includes an alkylene chain (a C₂₋₁₀alkylene chain) containing atleast one nitrogen atom in the main chain, a thioether chain (apolythioC₂₋₁₀alkylene ether chain such as a thioC₂₋₁₀alkylene etherchain and a dithioC₂₋₁₀alkylene ether chain), an ether chain (apolyoxyC₂₋₁₀alkylene ether chain such as an oxyC₂₋₁₀alkylene ether chainand a dioxyC₂₋₁₀alkylene ether chain), and the like. The hydrocarbonring includes an aromatic C₆₋₁₂hydrocarbon ring such as benzene; acycloalkane ring (a monocyclic alicyclic hydrocarbon ring), for example,a C₅₋₁₀cycloalkane ring such as cyclohexane; a crosslinked cyclichydrocarbon ring (e.g., a bi- or tricycloalkane ring such as norbornaneand adamantane; a C₅₋₁₀cycloalkene ring such as cyclohexene; a bi- ortricycloalkene ring such as norbornene); and the like. Moreover, ahydrocarbon ring may be a ring in which a plurality of hydrocarbon ringsmay be connected through a hydrocarbon chain if necessary (biphenyl; aring corresponding to a bis(C₆₋₁₄aryl)C₁₋₄alkane such asdiphenylmethane; etc.). For example, such a group may be exemplified asa group in which a chain hydrocarbon group (a linear or branchedC₂₋₄alkylene group or a linear or branched C₂₋₄alkenylene group, etc.)connects with a hydrocarbon ring group (an arylene group, acycloalkylene group, a bi- or tricycloalkylene group, etc.). Theheterocycle includes a heterocycle containing at least one heteroatomselected from oxygen, nitrogen and sulfur atoms, especially a 5- or6-membered heterocycle. Further, the chain or cyclic hydrocarbon groupsor the heterocycles and so on may have a substituent such as an alkylgroup (e.g., a C₁₋₅alkyl group) and a halogen atom.

In the formula (1), the coefficient p for the first connecting unit U₁is 0 or 1, and the coefficient t for the second connecting unit U₂ is aninteger of not less than 1 (especially 1 or 2).

The connecting unit U₁ may be a unit represented by the followingformula (3a), and the connecting unit U₂ may be a unit represented bythe following formula (3b).—(R¹)_(q)—(B)_(r)—  (3a)—(R²)_(u)—(Ar)_(v)—  (3b)(in the formula, each of the factors, R¹, R² and Ar, is either same ordifferent, representing a bivalent hydrocarbon group, and B represents abivalent bond such as an ester bond, a thioester bond, an amide bond, aurea bond, a urethane bond, a thiourethane bond and an imino group; abivalent atom such as an oxygen atom and a sulfur atom or a trivalentatom such as a nitrogen atom. Each of the factors, q, r, u and v,represents 0 or 1, and the total of q, r, u and v is not less than 1(q+r+u+v≧1)).

Incidentally, when B is nitrogen atom and r=1, t is 1 or 2, and when Bis an atom or a group other than nitrogen atom and r=1, t is usually 1.

As the bivalent hydrocarbon group represented by R¹, R² or Ar, there maybe exemplified, a bivalent group corresponding to the above-mentionedchain hydrocarbons (e.g., an alkylene group such as an ethylene group, apropylene group and trimethylene group, an alkenylene group such as avinylene group and an isopropenylene group) and a bivalent groupcorresponding to the above-mentioned hydrocarbon rings (e.g., acycloalkylene group, an arylene group (such as a phenylene group and anaphthalene group), a bi- or tricycloalkylene group, a biphenylenegroup, a group corresponding to a bisarylalkane) and the like. PreferredR¹ and R² are a chain hydrocarbon group such as a linear or branchedchain C₂₋₈alkylene group (especially a C₂₋₄alkylene group, etc.) and alinear or branched chain C₂₋₈alkylene group (especially a C₂₋₄alkylenegroup, etc.) and the like.

Preferred Ar is a hydrocarbon ring group, for example, an arylene groupsuch as a phenylene group and a naphthalene group, a biphenylene groupsuch as a biphenyl group, a bi- or tricycloalkylene group, a groupcorresponding to a bisarylalkane, and the like, and a C₆₋₁₂arylene group(a C₆₋₁₀arylene group) or C₅₋₈cycloalkylene group is especiallymentioned. The group Ar may have a substituent such as a halogen atom(e.g., fluorine atom, chlorine atom, bromine atom), an alkyl group(e.g., a C₁₋₄alkyl group), an alkoxy group (e.g., a C₁₋₄alkoxy group)and an acyl group (e.g., a C₁₋₄alkyl-carbonyl group).

In the formula, each of the factors, q, r, u and v, represents 0 or 1,and the total of q, r, u and v is not less than 1 (q+r+u+v≧1), andusually, q plus r is 0 to 2 (q+r=0-2) and u plus v is 1 to 2 (u+v=1-2).

A unit (U₁)_(p)—(U₂-Z)_(t) containing the connecting unit is, forexample, represented by the following formula (3):[(R¹)_(q)—(B)_(r)]_(p)—[{(R²)_(u)—(Ar)_(v)}-Z]_(t)  (3)(in the formula, R¹, R², B, Ar, p, q, r, t, u and v have the samemeanings defined above).

R¹ and R² may be exemplified the same group as the above-mentioned, andusually, an alkylene group (especially a C₂₋₄alkylene group) or analkenylene group (especially a C₂₋₄alkenylene group). B is an esterbond, an amide bond, a urea bond, a urethane bond, an imino group, asulfur atom or a nitrogen atom, and Ar is usually a hydrocarbon ringgroup (e.g., a C₆₋₁₀arylene group or a C₅₋₈cycloalkylene group),especially a benzene ring or a cyclohexane ring.

Such a metal alkoxide (1) may be obtained by a reacting of a compoundhaving a unit (X)_(m-n)M^(m) with a compound having the group Z, to forma connecting unit U between the metal M and the group Z, or may beobtained by a reaction of a compound having a unit (X)_(m-n)-M^(m)[especially, (X)_(m-n)-M^(m)-(R¹)_(q)] with a compound having a unitU₂-Z [especially, {(R²)_(u)—(Ar)_(v)}-Z]. Thus the connecting unit U₁ ismostly a connecting or binding group formed by these reaction, and theconnecting unit U₂ is mostly derived from a compound having a unit U₂.Various reactions can be used for the reaction of each component, forexample, there may be exemplified the following reactions by acombination of the reactive groups.

-   (i) an ester bond- (or a thioester bond-) forming reaction of a    hydroxyl group (or a mercapto group) or its lower alkyloxy group    with a carboxyl group or its reactive derivative group (e.g., an    acid anhydride group, an acid halide group, etc.); or a urethane    bond- (or a thiourethane bond-)forming reaction of a hydroxyl group    (or a mercapto group) with an isocyanate group,-   (ii) an ester bond- (or a thioester bond-) forming reaction of a    carboxyl group or its reactive derivative group with a hydroxyl    group (or a mercapto group) or its lower alkyloxy group; an ester    bond-forming reaction of a carboxyl group with an epoxy group; an    amide bond-forming reaction of a carboxyl group with an amino group;    or a ring-opening reaction of a carboxyl group with an oxazoline    ring,-   (iii) an amide bond- (or an imino bond-) forming reaction of an    amino group with a carboxyl group or its reactive derivative group    (e.g., an acid anhydride group, etc.); a reaction of an amino group    with an epoxy group (e.g., an imino bond-forming reaction, etc.); or    a urea bond-forming reaction of an amino group with an isocyanate    group,-   (iv) an addition reaction of a hydroxyl group, a mercapto group, an    amino group or a hydrogen atom (e.g., silyl group SiH), with a vinyl    group,-   (v) Hech reaction of a halogen atom with a vinyl group (e.g., a    coupling reaction of an alkene with a halogen-substituted aromatic    compound with the use of a palladium catalyst in the presence of a    base).

For example, in the case where the metal M is a silicon atom, as acompound having the unit (X)_(m-n)M, there may be exemplified, atriC₁₋₄alkoxysilane such as trimethoxysilane, triethoxysilane and atripropoxysilane; a C₁₋₄alkyldiC₁₋₄alkoxysilane such asmethyldimethoxysilane and methyldiethoxysilane; aC₆₋₁₀aryldiC₁₋₄alkoxysilane such as phenyldimethoxysilane andphenyldiethoxysilane; and other silane compounds having a functionalgroup such as an isocyanate group, an epoxy group, an amino group, amercapto group, a hydroxyl group, a carboxyl group and an unsaturatedbond (e.g., especially, a silane coupling agent).

The silane coupling agent includes a compound represented by thefollowing formula (4):(R⁶)_(u)Si(D)_(4-w)  (4)(In the formula, R⁶ represents an organic group having a reactive group,D represents a hydrogen atom, a halogen atom (fluorine atom, chlorineatom, bromine atom and iodine atom) or OR⁷. R⁷ represents an alkyl grouphaving 1 to 4 carbon atoms and w is an integer of 0 to 2.).

As the organic group represented by R⁶, there may be mentioned an alkylgroup having a reactive group (e.g., an isocyanatealkyl group, acarboxyalkyl group, an epoxyalkyl group, an aminoalkyl group, amercaptoalkyl group, a hydroxyalkyl group; an alkyl group having apolymerizable group such as a vinyl group, an allyl group and a(meth)acryloyl group, etc.) or an aryl group having a reactive group(e.g., an isocyanatearyl group, a carboxyaryl group, an aminoaryl group,a hydroxyaryl group; an aryl group having a polymerizable group such asa vinyl group, an allyl group and a (meth)acryloyl group, etc.); and thelike. The alkyl group represented by R⁷, there may be exemplified methylgroup, ethyl group, butyl group, t-butyl group.

As an isocyanate group-containing silane coupling agent, there may bementioned an isocyanatoalkylalkoxysilane (e.g., anisocyanatoC₁₋₆alkylC₁₋₄alkoxysilane) such as1-isocyanatomethyl-1,1,1-trimethoxysilane, 1-(1- or2-isocyanatomethyl)-1,1,1-trimethoxysilane,1-isocyanatomethyl-1,1,1-triethoxysilane, 1-(1- or2-isocyanatoethyl)-1,1,1-triethoxysilane,1-isocyanatomethyl-1-methyl-1,1-dimethoxysilane,1-chloro-1-isocyanatomethyl-1,1-dimethoxysilane,1-(3-aminopropyl)-1-isocyanatoethyl-1,1-dimethoxysilane,1-(3-aminopropyl)-1-isocyanatoethyl-1,1-diethoxysilane,1-isocyanatomethyl-1-phenyl-1,1-dimethoxysilane,1-isocyanatopropyl-1-phenyl-1,1-dipropoxysilane, and the like.

As an epoxy group-containing silane coupling agent, there may bementioned an epoxyalkylalkoxysilane (e.g., an epoxy group-containing aC₃₋₈alkyl-C₁₋₄alkoxysilane) such as1-(1,2-epoxypropyl)-1,1,1-trimethoxysilane and1-glycidyl-1,1,1-trimethoxysilane; a glycidoxyalkylalkoxysilane (e.g., aglycidoxyC₁₋₆alkylC₁₋₄alkoxysilane) such as1-(3-glycidoxypropyl)-1,1,1-trimethoxysilane and1-(3-glycidoxypropyl)-1-methyl-1,1-dimethoxysilane; and others.

As an amino group-containing silane coupling agent, there may bementioned an amino group-containing silane coupling agent correspondingto the isocyanate group-containing silane coupling agent, especially, anaminoalkylalkoxysilane (e.g., an aminoC₁₋₆alkyl-C₁₋₄alkoxysilane) suchas 1-(3-N-(2′-aminoethyl)aminopropyl)-1-methyl-1,1-dimethoxysilane,1-(3-N-(2′-aminoethyl)aminopropyl)-1,1,1-trimethoxysilane and1-(3-aminopropyl)-1,1,1-trimethoxysilane.

As a mercapto group-containing silane coupling agent, there may bementioned a mercapto group-containing silane coupling agentcorresponding to the isocyanate group-containing silane coupling agent,especially, an alkoxysilane having a mercapto group (e.g., amercaptoC₁₋₆alkyl-C₁₋₄alkoxysilane) such as1-(3-mercaptopropyl)-1,1,1-trimethoxysilane and1-(3-mercaptopropyl)-1,1,1-triethoxysilane, and others.

Moreover, a hydroxy group-containing silane coupling agent and acarboxyl group-containing silane coupling agent, corresponding to theisocyanate group-containing silane coupling agent can be also utilized.

As a silane coupling agent having an unsaturated bond, there may bementioned a silane coupling agent having a polymerizable group such as avinyl group, an allyl group and a (meth)acryloyl group, etc. The vinylgroup-containing silane coupling agent includes1-vinyl-1,1-dimethyl-1-ethoxysilane,1-vinyl-1-methyl-1,1-diethoxysilane, 1-vinyl-1,1,1-trimethoxysilane,1-vinyl-1,1,1-triisopropenoxysilane,1-vinyl-1,1-dimethyl-1-chlorosilane, 1-vinyl-1-ethyl-1,1-dichlorosilane,1-vinyl-1,1,1-trichlorosilane,1-vinyl-1-methyl-1,1-bis(methylethylketoximine)silane,1-vinyl-1-methyl-1,1-bis(trimethylsiloxy)silane,1-vinyl-1-methyl-1,1-diacetoxysilane, 1-vinyl-1,1,1-triphenoxysilane,1-vinyl-1,1,1-tris(t-butylperoxy)silane, and others. Moreover, an allylgroup-containing silane coupling agent and a (meth)acryloyl group- (or a(meth)acryloyloxy group-) containing silane coupling agent,corresponding to the vinyl group-containing silane coupling agent can bealso utilized. Incidentally, as the silane coupling agent, acommercially available silane coupling agent can be also available.

As a compound having a photo-crosslinkable (or photo-curable) group or acompound having a hydrophilic group, corresponding to the compoundhaving group Z or a unit U₂-Z (especially, R²—Ar-Z), there may beexemplified a compound having a reactive group [e.g., a group having anactive hydrogen atom such as a hydroxyl group, a carboxyl group and anamino group; an isocyanate group or a vinyl group (including a(meth)acryloyl group)], or a reactive atom (e.g., a halogen atom), inaddition to the photo-crosslinkable groups or the hydrophilic groups.

As a compound having a hydroxyl group, there may be exemplified analiphatic polyhydroxy compound (e.g., a linear or branched C₂₋₁₀alkyleneglycol such as ethylene glycol, trimethylene glycol, propylene glycoland tetramethylene glycol; a polyoxyC₂₋₄alkylene glycol such as a di- topolyethylene glycol and a di- to polypropylene glycol), an aromaticpolyhydroxy compound [e.g., a phenol such as hydroquinone, resorcin,catechol, phloroglucin, oxyhydroquinone, pyrogallol, an alkylester ofgallic acid (e.g., a C₁₋₄alkylester of gallic acid); a hydroxyaralkylalcohol (e.g., a hydroxyC₆₋₁₀aryl-C₁₋₄alkyl alcohol) such as xylyleneglycol and hydroxybenzyl alcohol; a hydroxybenzophenone, ahydroxynaphthalene such as a naphthalene diol and a naphthalene triol; abiphenol, a bisphenol (e.g., a bisphenol A, a bisphenol F, a bisphenolAD, etc.)], an alicyclic polyhydroxy compound [a monocyclic alicyclicdiol (e.g., a C₅₋₈cycloalkanediol such as cyclohexanediol; aC₅₋₈cycloalkenediol such as a cyclohexenediol; a cyclohaxenedimethanol),a crosslinked alicyclic diol (e.g., a bi- or tricycloalkanediol such asa norbornanediol and an adamantanediol)], a heterocyclic polyhydroxycompound [a 5- to 8-membered unsaturated heterocyclic polyhydroxycompound (e.g., a 5- or 6-membered unsaturated heterocyclic di- ortrihydroxy compound) such as a dihydroxypyran and a dihydroxyfuran; a 5-to 8-membered saturated heterocyclic polyhydroxy compound (e.g., a 5- or6-membered saturated heterocyclic di- or trihydroxy compound, especiallya dihydroxyoxacycloalkane) such as a dihydroxytetrahydrofuran and adihydroxytetrahydropyran; etc.] a compound having a hydroxyl group and ahalogen atom (bromine atom, iodine atom, etc.) [e.g., a halogenatedalcohol (a halogenated C₁₋₁₀alkyl alcohol etc.), a halogenated phenol(e.g., a haloC₆₋₁₀aryl alcohol such as a bromophenol and an iodophenol),a halogenated cycloalkanol (e.g., a halogenated C₅₋₆cycloalkanol such asa iodohexanol)], a compound having a hydroxyl group and a carboxyl group[a hydroxycarboxylic acid, for example, ahydroxyaliphaticC₂₋₁₂carboxylic acid (e.g., a hydroxycaproic acid), ahydroxyaromaticC₆₋₁₀carboxylic acid (e.g., salicylic acid, adihydroxybenzoic acid, gallic acid, a hydroxynaphthoic acid), ahydroxyC₅₋₆cycloalkane-carboxylic acid (e.g., ahydroxycyclohexanecarboxylic acid)], a compound having a hydroxyl groupand an amino group [e.g., an aminoC₂₋₁₀alkyl alcohol such as anethanolamine and a propanolamine, an aminophenol (an aminoC₆₋₁₀arylalcohol such as an aminophenol, an aminocresol and an aminosalicylicacid, an aminoC₅₋₆cycloalkanol, etc.] a compound having a hydroxyl groupand an epoxy group (e.g., a glycidylC₆₋₁₀aryl alcohol such as aglycidylphenol), a compound having a hydroxyl group and a vinyl,(meth)acryloyl or allyl group (e.g., a vinylC₆₋₁₀aryl alcohol such as avinylphenol, a hydroxyC₂₋₆alkyl(meth) acrylate, an ally alcohol), andothers.

As a compound having a carboxyl group, there may be mentioned apolycarboxylic acid [e.g., a C₁₋₁₂alkane-dicarboxylic acid (e.g., adipicacid, pimelic acid, sebacic acid and azelaic acid), an aromaticdicarboxylic acid (e.g., a benzene dicarboxylic acid, a naphthalenedicarboxylic acid), a C₅₋₆cycloalkane-dicarboxylic acid (e.g., acyclohexanedicarboxylic acid)], a compound having a carboxylic group andan amino group [an aminoC₂₋₁₀alkyl-carboxylic acid, anaminoC₆₋₁₀aryl-carboxylic acid (e.g., an aminobenzoic acid), anaminoC₅₋₆cycloalkyl-carboxylic acid (e.g., an aminocyclohexanecarboxylicacid)], a compound having a carboxyl group and a halogen atom (e.g., ahalogenated aliphaticC₂₋₁₀carboxylic acid, a halogenatedC₆₋₁₀aryl-carboxylic acid such as a chlorobenzoic acid and aniodobenzoic acid, a halogenated C₅₋₆cycloalkyl-carboxylic acid such as achlorocyclohexanecarboxylic acid and an iodocyclohexanecarboxylic acid),a compound having a carboxyl group and an epoxy group (a glycidylgroup-containing C₆₋₁₀aryl-carboxylic acid such as a glycidylbenzoicacid), a compound having a carboxyl group and a vinyl, (meth)acryloyl orallyl group [e.g., a (meth)acrylic acid; a vinyl group-containingC₆₋₁₀aryl-carboxylic acid such as a vinylbenzoic acid; an unsaturatedpolycarboxylic acid such as itaconic acid, maleic acid and fumaric acidor a monoalkylester thereof; etc.], and the like.

As a compound having an amino group, there may be mentioned a diamine,for example, an aliphatic diamine [e.g., a C₂₋₁₀alkanediamine such asethylenediamine, propylenediamine, 1,4-diaminobutane,hexamethylenediamine, 2,5-dimethylhexamethylenediamine), an aromaticdiamine (e.g., a C₆₋₁₀arylenediamine such as a methaphenylenediamine anddiaminodiphenylmethane; a xylylenediamine (aC₁₋₄alkyl-C₆₋₁₀arylene-C₁₋₄alkyl)diamine, etc.)], an alicyclic diamine(e.g. menthenediamine, isophorone diamine and a diaminoC₅₋₆cycloalkanesuch as a diaminodicyclohexylmethane), and the like.

As a compound having a halogen atom, there may be mentioned adihaloC₂₋₁₀alkane (such as a diiodohexane), a C₆₋₁₀aromatic dihalide(such as a diiodobenzene), a dihaloC₅₋₆cycloalkane (such as adiiodocyclohexane), and the like. As a compound having a vinyl group,there may be mentioned a C₆₋₁₀aromatic divinyl compound such as adivinylbenzene, and the like. As a compound having an isocyanate group,there may be mentioned an aliphatic diisocyanate such ashexamethylenediisocyanate; an aromatic diisocyanate such as atolylenediisocyanate and xylylenediisocyanate; an alicyclic diisocyanatesuch as isophoronediisocyanate; and the like.

In the case of using these compounds, it is easy to control the affinitywith a base resin and the solubility to a developer. Incidentally, inthese compounds, a hydrophilic group HP (e.g., a hydroxyl group, acarboxyl group) may be protected by a protective group Pro in advance,before reacting it with a compound having a unit (X)_(m-n)M^(m), or maybe protected by a protective group Pro after reacting it with a compoundhaving a unit (X)_(m-n)M^(m). That is, the group Z causing thedifference in solubility may be a group -HP-Pro [in the formula, HPmeans a hydrophilic group and Pro means a protective group removing((eliminating or leaving)) by light exposure and forming the hydrophilicgroup (in particular, a protective group imparting a hydrophobicity tothe hydrophilic group. Incidentally, the protective group can beintroduced by a conventional method, for example, various methods suchas an acetalized reaction, an esterification method, an activeesterification method, a mixed acid anhydride method, an azide method, amethod using a coupling agent (e.g., dicyclohexylcalboziimide (DCC)method, DCC-additive method, etc.), and the like.

As a protective group Pro of the hydrophilic group HP, there may bementioned a protective group for a hydroxyl group, for example, anacetal-series protective group such as an alkoxyalkyl group [e.g., aC₁₋₆alkoxy-C₁₋₆alkyl group (such as 1-methoxyetyl group, 1-ethoxypropylgroup and 1-methoxy-isopropyl group), preferably a C₁₋₄alkoxy-C₁₋₄alkylgroup); an acyl group such as an alkylcarbonyl group (e.g., aC₁₋₆alkyl-carbonyl group such as acetyl, propyonyl, isopropyonyl,butyly, t-butylcarbonyl group and isovaleryl group, preferably aC₁₋₄alkyl-carbonyl group), a cycloalkylcarbonyl group (e.g., aC₅₋₈cycloalkyl-carbonyl group such as cyclohexylcarbonyl group,preferably a C₅₋₆cycloalkyl-carbonyl group), an arylcarbonyl group(e.g., a C₆₋₁₀aryl-carbonyl group such as benzoyl group); aC₁₋₆alkoxy-carbonyl group (e.g., a C₁₋₄alkoxy-carbonyl group) such asmethoxycarbonyl group, ethoxycarbonyl group and t-butoxycarbonyl (t-BOC)group; an aralkyloxy carbonyl group such as benzyloxycarbonyl group(e.g., a C₆₋₁₀aryl-C₁₋₄alkyloxy-carbonyl group); a C₅₋₈cycloalkyl groupsuch as cyclohexyl group (e.g., a C₅₋₆cycloalkyl group); an aryl groupsuch as 2,4-dinitrophenyl group (e.g., a nitro group-substituted phenylgroup); an aralkyl group such as a benzyl group, a 2,6-dichlorobenzylgroup, a 2-nitrobenzyl group and a triphenylmethyl group (e.g., aC₆₋₁₀aryl-C₁₋₄alkyl group which may have a substituent); an acetal group(a diC₁₋₆alkoxy group such as a dimethoxy, diethoxy and1-methoxy-l-butoxy group); an oxacycloalkyl group such as atetrahydrofuranyl group and a tetrahydropiranyl group (e.g., a 5- to8-membered oxacycloalkyl group); a crosslinked cyclic alicyclichydrocarbon group such as a norbornyl group, an admantyl group and ahydrogenated naphthyl group (e.g., a bi- to tetracycloalkyl group), andthe like.

Further, as a protective group for a carboxyl group, there may bementioned, for example, a C₁₋₆alkyl group (e.g., a C₁₋₄alkyl group) suchas methyl group, ethyl group and t-butyl group; a carbamoyl group whichmay have a substituent (e.g., an alkyl group, an aryl group,etc.)(carbamoyl group; a C₁₋₆alkyl-carbamoyl group such asmethylcarbamoyl group and ethylcarbamoyl group (preferably aC₁₋₄alkyl-carbamoyl group); a C₆₋₁₀arylcarbamoyl group such asphenylcarbamoyl group); a crosslinked cyclic alicyclic hydrocarbon groupsuch as a norbornyl group, an admantyl group and a hydrogenated naphthylgroup (e.g., a bi- to tetracycloalkyl group); adiC₁₋₄alkylphosphinothioyl group such as a dimethylphosphinothioylgroup; a diC₆₋₁₀arylphosphinothioyl group such as adiphenylphosphinothioyl group; and the like.

In particular, the protective group Pro is preferable to be ahydrophobic protective group which imparts hydrophobicity to thehydrophilic group HP. As the protective group for a hydroxyl group, thefollowing groups are preferred, for example, an acyl group (especially,a C₁₋₄alkyl-carbonyl group such as t-butylcarbonyl group), analkoxycarbonyl group (a C₁₋₄alkoxycarbonyl group such as t-BOC group), a5- or 6-membered oxacycloalkyl group (such as a tetrahydropiranylgroup), a bi- or tricycloalkyl group (such as a norbornyl group and anadmantyl group), a C₁₋₄alkoxy-C₁₋₄alkyl group. As the protective groupfor a carboxyl group, the following groups are preferred, for example,an alkyl group (a C₁₋₄alkyl group such as a t-butyl group), a carbamoylgroup which may have a substituent; a crosslinked cyclic alicyclichydrocarbon group such as a norbornyl group, an admantyl group and ahydrogenated naphthyl group (e.g., a bi- to tetracycloalkyl group).

In each of the above-mentioned reactions, a conventional catalyst orsolvent can be utilized if necessary. As the catalyst, depending on thespecies of the reactions, there may be used, for example, an acid (e.g.,an inorganic acid such as hydrochloric acid and sulfuric acid; anorganic acid such as p-toluenesulfonic acid), a base (e.g., an organicamine such as tertiary amine, etc.), a conventional catalyst foracetalization (e.g., hydrogen chloride, manganese dioxide, sulfuricacid, etc.), and a catalyst for addition reaction (e.g., a transitionmetal catalyst such as a palladium catalyst). As the solvent, there maybe used, for example, water, an organic solvent such as an alcohol, aglycol, a cellosolve, a ketone, an ester, an ether, an amide, ahydrocarbon, a halogenated hydrocarbon, a carbitol and an ester ofglycol ether (e.g., a cellosolve acetate and propylene glycol monomethylether acetate). Incidentally, in the case of using a component having anisocyanate group, for example, the reaction is preferably conducted in acondition where activity of the isocyanate group can be maintained(e.g., in the absence of moisture, or in the presence of moisture at aamount which does not substantially interfere the activity of theisocyanate group, especially, in nonaqueous system).

In the formula (1), the following combinations may be mentioned as apreferable combination of groups:

-   X: a C₁₋₄alkoxy group, a halogen atom (especially, a C₁₋₂alkoxy    group),-   Z: a hydroxyl or carboxyl group protected by a hydrophobic    protective group which is capable of removing (removable) owing to    light exposure,-   M: a metal atom selected from the group consisting of aluminum,    titanium, zirconium and silicon,-   (U₁)_(p)—(U₂-Z)_(t): a unit represented by the above-mentioned    formula (3),-   n=1 or 2,-   p=0 or 1 (q+r=0 to 2), and-   t=1 or 2 (u+v=1 to 2)    (Polycondensate or Active Particle of an Active Metal Alkoxide (1b))

An active component (especially an active particle) of the presentinvention may comprise a polycondensate of the above-mentioned activemetal alkoxide. Such an active component may be an active particle inthe form of a particulate (particulate matter), or a liquid or solidoligomer. The active component, the polycondensate of the activecomponent can be obtained by polycondensing the active metal alkoxide bya conventional sol-gel method to form of a polymer or a sol.

More concretely, the process for producing the active componentcomprises dissolving a metal alkoxide component comprising at least anactive metal alkoxide to an organic solvent, adding water thereto andstirring the mixture in the presence of a polymerizable catalyst. As theorganic solvent, such a hydrophilic or water-soluble solvent can beused, for example, an alcohol (e.g., methanol, ethanol and isopropanol),a ketone (e.g., acetone), an ester [e.g., ethyl acetate; an ester oflactic acid such as ethyl lactate; a (poly)oxyalkylene glycol alkylether acetate such as propylene glycol methyl ether acetate (PGMEAetc.); etc.], a cellosolve (e.g., a methylcellosolve, a ethylcellosolveand a butylcellosolve), and the like. These solvents may be same with asolvent of a resist solution (e.g., ethyl lactate and PGMEA).

The proportion of water is, relative to 1 mol of the metal atom in themetal alkoxide component, about 0.1 to 10 mmol, preferably about 0.2 to5 mmol and more preferably about 0.5 to 2 mmol.

As the polymerizable catalyst, there may be used, for example, an acid(e.g., an inorganic acid such as hydrochloric acid, sulfuric acid,nitric acid and a phosphoric acid; an organic acid such as a aceticacid; etc.), or a base (e.g., an inorganic base such as an ammonia, anorganic base such as an amine, etc.), and the like. The proportion ofthe catalyst is, relative to 1 mol of metal atom in the metal alkoxidecomponent, about 0.001 to 0.1 mmol, preferably about 0.005 to 0.05 mmol.

The polymerization temperature may be about 0 to 40° C. (e.g., 10 to 35°C.), preferably a room temperature (about 15 to 30° C.). Thepolymerization pressure is not especially limited, may be normalpressure (or atmospheric pressure), increased pressure (pressurization),or reduced pressure (depressurization), usually normal pressure. Thepolymerization time is not especially limited, may be selected withinthe wide range from 5 minutes to 1 day, and is preferably from 10minutes to 12 hours, preferably from 30 minutes to 10 hours.

The metal alkoxide component may comprise a metal alkoxide representedby the following formula (5) in addition to the active metal alkoxide.That is, the active metal alkoxide may be copolycondensed with the metalalkoxide (5).(X)_(m-n-1)M^(m)(R⁵)_(n-1)  (5)(In the formula, R⁵ represents a hydrogen atom or an alkyl group. X, M,m and n have the same meanings defined above.)

In the formula (5), an alkyl group represented by R⁵ may be exemplifiedby the alkyl groups similar to those mentioned above, especially amethyl group or an ethyl group is preferable. X is usually a halogenatom or an alkoxy group.

In the case of copolycondensing with the metal alkoxide (5), the weightratio of an active metal alkoxide (1) relative to a metal alkoxide (5)can be selected within the range of, for example, about 5/90 to 90/10(e.g., about 10/90 to 90/10), and is usually about 5/90 to 80/20 (e.g.,about 5/95 to 60/40), preferably about 10/90 to 50/50, and morepreferably about 20/80 to 40/60.

The mean particle size of the particulate active component (activeparticle) can be adjusted by a degree of polymerization, depending onthe degree of miniaturization of a pattern, for example, can be selectedfrom the range of about 1 to 500 nm (e.g., about 1 to 100 nm),preferably 1 to 50 nm in accordance with BET method. The preferred meanparticle size of the active particle is usually about 2 to 30 nm andpreferably about 3 to 25 nm (e.g., about 5 to 25 nm). In particular,since making the smaller mean particle size of the active particleensures thinning a photosensitive layer, resolution can be improved asmuch as edge roughness can be reduced. Further, when the mean particlesize of the active particle is smaller than an exposing wavelength,because the active particle is substantially transparent to the exposingwavelength, light exposure can be conducted to the depth of thephotosensitive layer even if the layer is thickened, and as a result,sensitivity and resolution can be improved as much as a pattern withhigh sensitivity and high resolution can be formed in regard to a lightsource of shorter wavelength.

[Active Particle (2) having a Fine Particle Carrier]

The particle represented by the formula (2) comprises a fine (minute)particle carrier and a unit which directly or indirectly bonds to thecarrier and causes a difference in solubility by light exposure(especially, a unit which can become hydrophilic by removing(eliminating or leaving) a protective group by light exposure). In theunit, the protective group can be usually removed (eliminated) inassociation with a photosensitizer by light exposure.

In the above-mentioned formula (2), the connecting unit represented byU₁ and U₂, and the group represented by Z may be exemplified by theconnecting unit and the group Z or coefficients mentioned in the sectionof the formula (1), the coefficient p and t have the same meaningsdefined above.

The active particle may be a particle in which s and p are s=p=0 in theformula (2) (e.g., a particle wherein a hydrophilic group of a fineparticle carrier such as an organic fine particle is protected by aprotective group), or a particle in which at least one factor selectedfrom s and p is 1. Moreover, in the formula (2), k is a value whichdepends on a concentration of a reactive group (e.g., a hydrophilicgroup) of carrier and an introduction amount of the group Z by thecoupling agent. Incidentally, the coupling agent usually corresponds toa compound having a metal atom M in the formula (1).

More concretely, there may be mentioned the case in which the group Z isa hydrophilic group HP protected by a protective group Pro. For example,in a carrier P having a reactive group, (a) in the case where thereactive group is a hydrophilic group, the hydrophilic group may beprotected by a protective group (s=p=0), and (b) in the case where thereactive group is not a hydrophilic group, the hydrophilic group HP maybe protected by a protective group Pro by introducing the hydrophilicgroup HP through a connecting unit U₁ and/or a connecting unit U₂ (s=0,p=1 and/or t=1). Moreover, in the case where the carrier P is a fineparticle such as an inorganic fine particle, the reactive group may beintroduced with the use of a coupling agent, and (c) in the case wherethe reactive group is a hydrophilic group HP, this hydrophilic group HPmay be protected by the protective group Pro (s=1, t=0), (d) in the casewhere the introduced reactive group is not a hydrophilic group, thehydrophilic group HP may be protected by a protective group Pro byintroducing a hydrophilic group HP through a connecting unit U₁ (s=1,p=1, t=1). Incidentally, in the present specification, a unit—U₂-HP—issometimes referred to as a hydrophilizable unit.

As the reaction of each component, i.e., the fine particle carrier P,the coupling agent Y, the connecting units U₁ and U₂, various reactionsmay be utilized, and there may be mentioned, for example, a reaction bythe above-mentioned combinations of the reactive groups, concretely, amethod which can be utilized for a reaction of a compound having theunit (X)_(m-n)M^(m) or (X)_(m-n)-M^(m)-(R¹)_(q) with a compound havingthe group Z or a compound having the unit U₂-Z or {(R²)_(u)—(Ar)_(v)}-Z,for example, (i) the ester bond-(thioester bond-) forming reaction, orthe urethane bond- (or a thiourethane bond-) forming reaction, (ii) theester bond- (or a thioester bond-) forming reaction, the amidebond-forming reaction or the ring-opening reaction, (iii) the amidebond- (or an imino bond-) forming reaction, the reaction of an aminogroup with an epoxy group (e.g., an imino bond-forming reaction, etc.)or the urea bond-forming reaction, (iv) the addition reaction, and (v)the coupling reaction such as Hech reaction.

Hereinafter, the case introducing a hydrophilic group into an inorganicfine particle through both a coupling agent and a connecting unit istaken as an example and explained. For example, each component may bebonded by reacting a connecting unit U having two hydroxyl groups (e.g.,a dihydroxy compound such as resorcin) with a coupling agent Y having anisocyanate group (e.g., a silane coupling agent) to form a compoundhaving a free hydroxyl group and a coupling group (an alkoxy group or ahalogen atom), wherein the coupling agent is bonded to one of hydroxylgroups of the unit; protecting the free hydroxyl group by a protectivegroup such as t-BOC group; and then reacting an inorganic fine particlecarrier (e.g., silicasol, etc.) with the coupling group (the alkoxygroup or the halogen atom). Further, for example, other processes may beemployed, that is, protecting a hydroxyl group of a compound having ahalogen atom (iodine atom, bromine atom, etc.) and a hydroxyl group(e.g., a halogen-containing aromatic hydroxy compound such as4-iodophenol) by a protective group such as t-BOC group in advance;subjecting the resultant compound to a coupling reaction with a vinylgroup-containing silane coupling agent (e.g.,methacryloxypropyltrimethoxysilane) by Hech reaction to bind thecompound with an inorganic fine particle carrier via the alkoxy group orhalogen atom site in the silane coupling agent. Incidentally, the orderof each reaction among each component is not particularly limited, forexample, a carrier may be reacted with a coupling agent in advance andthen the resultant may be reacted with other components. Moreover, inthe case of using a component having an isocyanate group, for example,the reaction is preferably conducted under the condition where theactivity of the isocyanate group can be maintained (e.g., in the absenceof moisture, or in the presence of moisture at a amount which does notsubstantially interfere the activity of the isocyanate group,especially, in nonaqueous system).

In each reaction step, a conventional catalyst or a solvent may be usedif necessary. As the solvent, there may be used, for example, water, anorganic solvent such as an alcohol, a glycol, a cellosolve, a ketone, anester, an ether, an amide, a hydrocarbon, a halogenated hydrocarbon, acarbitol and an ester of glycol ether (e.g., a cellosolve acetate and apropylene glycol monomethyl ether acetate).

Hereinafter, as a typical active component shown in the formula (2), aactive particle, in which the group Z is a hydrophilic group HPprotected by the protective group Pro, is taken as an example andexplained.

As the hydrophilic group HP, there may be exemplified a water- oralkali-soluble group such as hydroxyl group, carboxyl group and asulfur-containing derivative group thereof (e.g., mercapto group, athiocarboxyl group and dithiocarboxyl group), in addition to amino groupand an N-substituted amino group (e.g., a N,N-diC₁₋₄alkylamino group)and the like, and especially, the hydroxyl group (e.g., a phenolichydroxyl group) and the carboxyl group are preferred.

As the fine particle carrier P, an organic fine particle [athermoplastic resin which may be crosslinked (e.g., a styrenic resinwhich may be crosslinked such as a crosslinked polystyrene, astyrene-(meth)acrylic acid copolymer and a styrene-malefic anhydridecopolymer; an (meth)acrylic resin which may be crosslinked such as acrosslinked polymethyl methacrylate and a methylmethacrylate-(meth)acrylic acid copolymer; a silicone resin; athermosetting resin which may be crosslinked or cured such as apolyamide resin, a crosslinked melamine resin and a crosslinkedguanamine resin, etc.] can be also employed. The fine particle carrier Pmay have a hydrophilic group such as a hydroxyl group and a carboxylgroup, and the concentration of these hydrophilic groups may be adjustedaccording to the amount to be used of a monomer having the hydrophilicgroup. It is advantageous to use an inorganic fine particle forimproving the properties such as heat resistance and dry etchingresistance.

As the inorganic fine particle carrier, for example, there may beutilized, a metal alone (simple or single metal) (e.g., gold, silver,copper, platinum, aluminium), an inorganic oxide (e.g., silica (e.g.,silica sol such as colloidal silica, aerogels, glass), alumina, titania,zirconia, zinc oxide, copper oxide, lead oxide, yttrium oxide, tinoxide, indium oxide, magnesium oxide), an inorganic carbonate (e.g.,calcium carbonate and magnesium carbonate), an inorganic sulfate (e.g.,barium sulfate and calcium sulfate), a phosphate (e.g., calciumphosphate and magnesium phosphate), and the like. The inorganic fineparticle carriers include sols and gels prepared by, for example, asol-gel method. These inorganic fine particle carriers can be usedeither singly or in combination.

Use of the fine particle carriers enhances development efficiency by adeveloper because developers may be permeated (infiltrated) between fineparticles.

The shape of the fine particle carriers is not limited to sphere and maybe spheroid, disk, rod-like, or fibrous. The mean particle size of thefine particle carriers, depending on the degree of minuteness of apattern to be formed, for example, can be selected within the range ofabout 1 to 1,000 nm, preferably 5 to 500 nm (e.g., 1 to 100 nm) and morepreferably 1 to 50 nm (e.g., 5 to 50 nm) in accordance with the BETprocess. In particular, since making the smaller mean particle size ofthe active particle ensures thinning a photosensitive layer, resolutioncan be improved as much as edge roughness can be reduced. Further, whena fine particle carrier (e.g., silicasol) having smaller mean particlesize of the active particle than an exposing wavelength is used, becausethe active particle is substantially transparent to the exposingwavelength, light exposure can be conducted to the depth of thephotosensitive layer even if the layer is thickened, and as a result,sensitivity and resolution can be improved as much as a pattern withhigh sensitivity and high resolution can be formed in regard to a lightsource of shorter wavelength. Incidentally, such a silicasol iscommercially available as an organosol (an organosilicasol). Forexample, the organosol is available from Nissan Chemical Industries,Ltd. as the tradename “Snowtex collidalsilica”.

As a coupling agent corresponding to a residue Y of the coupling agent,for example, there may be exemplified an organic metal compoundcontaining, as the metal M, an alkaline earth metal, a transition metal,a rare earth metal, or a metal element of the Groups 3 to 5 and 13 to 15of the Periodic Table of Elements, especially a metal element of theGroups 4, 13 and 14 of the Periodic Table of Elements, for example,aluminium, titanium, zirconium, silicon. Among the organic metalcompounds, a titanium coupling agent and a silane coupling agent(especially the silane coupling agent) are preferred.

The silane coupling agent includes the coupling agents represented bythe formula (4). The reactive group D corresponding to the fine particlecarrier of the coupling agent (4) is usually a halogen atom (bromineatom, chlorine atom, etc.), a hydrolytic condensable group such as analkoxy group (e.g., a C₁₋₄alkoxy group such as methoxy group and ethoxygroup, especially a C₁₋₂alkoxy group) represented by OR⁷ (R⁷ representsa C₁₋₄alkyl group).

The silane coupling agent includes the above-mentioned coupling agents[e.g., the isocyanate group-containing silane coupling agents, the epoxygroup-containing silane coupling agents, the amino group-containingsilane coupling agents, the mercapto group-containing silane couplingagents, the hydroxyl group-containing and carboxyl group-containingsilane coupling agents corresponding to the isocyanate group-containingsilane coupling agents, the vinyl group-containing coupling agents, theallyl group-containing silane coupling agents and the (meth)acryloylgroup-containing silane coupling agents].

As the organic metal compound containing, as the metal M, aluminium,titanium or zirconium, there may be exemplified the organic metalcompounds corresponding to the above-mentioned silane coupling agents.

The ratio of the coupling agent relative to the inorganic fine particlecarrier can be selected from the range of, for example, about 0.1 to 200parts by weight, preferably about 0.5 to 150 parts by weight, morepreferably about 1 to 100 parts by weight relative to 100 parts byweight of the inorganic fine particle carrier.

The connecting unit U includes the above-mentioned units [e.g., a unitcontaining a chain hydrocarbon (e.g., a linear or branched C₁₋₁₀alkylenechain such as a C₂₋₆alkenylene chain), a hydrocarbon ring (an aromaticC₆₋₁₂hydrocarbon ring such as a benzene ring (e.g., an aromaticC₆₋₁₀hydrocarbon ring), a C₅₋₁₀cycloalkane ring, a C₅₋₁₀cycloalkenering, a crosslinked cyclic hydrocarbon ring (e.g., a bi- ortricycloalkane ring), a ring wherein a plurality of hydrocarbon chainsand/or hydrocarbon rings are bonded (e.g., aC₆₋₁₄aryl-C₁₋₄alkyl-C₆₋₁₄aryl, etc.), a heterocycle (e.g., a heterocyclecontaining at least one hetero atom selected from an oxygen atom, anitrogen atom and a sulfur atom)].

The connecting unit U may have a substituent as far as thecharacteristic of the active component is not inhibited. Incidentally,in the case where the unit has a substituent (e.g., an alkyl group, acycloalkyl group and an aryl group), affinity to or compatibility with abase resin can be improved and uniform dispersion of the activecomponent in the photosensitive resin composition can be attained, andalso, the difference in solubility between exposed-area and non-exposedarea relatively seems to be enlarged.

The compound corresponding to the hydrophilizable unit (—U₂-HP-)includes a compound having an active hydrogen atom such as a hydroxylgroup, a carboxyl group and an amino group, for example, theabove-exemplified compounds [e.g., a compound having plural hydroxylgroups, a compound having plural carboxyl groups, a compound having ahydroxyl group and a carboxyl group, a compound having a hydroxyl groupand an amino group, a compound having a carboxyl group and an aminogroup]. The compound may have a reactive halogen atom like theabove-exemplified compounds having a halogen atom. Moreover, thecompound may be the above-exemplified compound having an isocyanategroup.

With using such a compound, affinity to a base resin or solubility to adeveloper is easy to control. Incidentally, in these compounds, asmentioned above, the hydrophilic group HP (e.g., a hydroxyl group and acarboxyl group) may be protected by the protective group Pro in advance,or may be protected by the protective group Pro after introduction ofthe hydrophilic group HP. As the protective group Pro for thehydrophilic group HP, there may be mentioned the above-exemplifiedprotective groups.

In particular, a hydrophobic protective group which impartshydrophobicity to the hydrophilic group is preferable. For example, as aprotective for a hydroxyl group, the following groups are preferable, anacyl group (especially an alkylcarbonyl group such as a t-butylcarbonylgroup), an alkoxycarbonyl group (a C₁₋₆alkoxycarbonyl group such ast-BOC group), an acetal group (e.g., a diC₁₋₆alkoxy group), a 5- or6-membered oxacycloalkyl group (e.g., a tetrahydropiranyl group), a bi-or tricycloalkyl group (e.g., a norbornyl group and an adamantyl group),a C₁₋₄alkoxy-C₁₋₄alkyl group and the like. As a protective group for thecarboxyl group, an alkyl group (a C₁₋₄alkyl group such as t-butylgroup), a carbamoyl group which may have a substituent and a bi- ortricycloalkyl group (e.g., a norbornyl group and an adamantyl group) arepreferred.

Thus, also in the particle represented by the formula (2), the group Zto cause (generate) the difference in solubility is usually a group-HP-Pro [in the formula, HP represents a hydrophilic group, Prorepresents a protective group forming the hydrophilic group HP byremoving (eliminating or leaving) owing to light exposure (especially, aprotective group which imparts hydrophobicity to the hydrophilic groupHP)].

In the particle represented by the formula (2), as a combination ofpreferable groups, the following combinations may be exemplified.

-   P: an inorganic fine particle,-   Y: a silane coupling residue,-   (U₁)_(p)—(U₂-Z)_(t): a unit represented by the above-mentioned    formula (3),-   Z: a group -HP-Pro (in the formula, HP represents a hydrophilic    group (especially a hydroxyl group or a carboxyl group), Pro    represents a protective group which imparts hydrophobicity to the    hydrophilic group HP and causes (generates) the hydrophilic group HP    by removing (eliminating or leaving) owing to light exposure,-   s: 1,-   p; 0 or 1, and-   t: an integer of not less than 1 (especially 1 or 2).

The especially preferable particle comprises a connecting unit bondingto an inorganic fine particle having a mean particle size of 1 to 50 nmthrough a silane coupling agent; a hydrophilic group bonding to theconnecting unit; and a protective group protecting the hydrophilicgroup, and the group Z which causes the difference in solubility bylight exposure comprises the hydrophilic group(s) and the protectivegroup(s). Moreover, the connecting unit usually comprises at least onemember selected from the group consisting of an aromaticC₆₋₁₂hydrocarbon ring, a monocyclic alicyclic hydrocarbon ring, acrosslinked alicyclic hydrocarbon ring and an aliphatic hydrocarbonchain, and the hydrophilic group is a hydroxyl group or a carboxylgroup. Further, the protective group is usually (i) a protective groupfor the hydroxyl group selected from a C₁₋₄alkyl-carbonyl group, aC₁₋₄alkoxy-C₁₋₄alkyl group, a C₁₋₄alkoxy-carbonyl group, a 5- or6-membered oxacycloalkyl group and a bi- or tricycloalkyl group, or (ii)a protective group for the carboxyl group selected from a C₁₋₄alkylgroup, a carbamoyl group, a C₁₋₄alkyl-carbamoyl group, aC₆₋₁₀aryl-carbamoyl group and a bi- or tricycloalkyl group.

Incidentally, the particle represented by the formula (2) may be aparticle wherein the active metal alkoxide binds to theabove-exemplified fine particle carrier. That is, the particle may be aparticulate active component obtained by a coupling reaction of the fineparticle carrier with the active metal alkoxide represented by theformula (1) with the use of the group X (e.g., an alkoxy group, ahalogen atom, etc.) in the active metal alkoxide represented by theformula (1).

[Active Component]

The active component (or the photoactive component) of the presentinvention is advantageously used (usable) in combination with aphotosensitive resin composition. The active component, i.e., the activemetal alkoxide or its polycondensate (an oligomer or an active particle)represented by the formula (1) and an active particle represented by theformula (2), can be utilized either singly or in combination.

When the active component (1) is used (usable) in combination with aphotosensitizer of a photosensitive resin composition, because of thegroup Z of the active metal alkoxide, which is introduced into theactive component, a difference in solubility can be caused (made orgenerated) by light exposure. For example, (a) in the case where thegroup Z is a photosensitive group such as a crosslinkable group, whenthe active component is applied to a negative resist in combination witha photosensitizer such as a photoactive acid generator and acrosslinking agent, a photopolymerization initiator, crosslinking orpolymerization occurs in an exposed area to inhibit dissolution in theexposed area, and as a result, the difference in solubility betweenexposed area and non-exposed area occurs.

Further, in the active component (1), (2), the protective group iscapable of removing (removable) by light exposure, especially inassociation with a photosensitizer constituting a photosensitive resincomposition by light exposure. (b) In the case where the group Z is ahydrophilic group protected by a protective group capable of removing(removable) owing to light exposure, the protective group is eliminated(or deprotected) by light exposure (especially, in association with aphotosensitizer owing to light exposure) to cause (make) a hydrophilicgroup such as a hydroxyl group or a carboxyl group, by using the activecomponent in combination with a photosensitizer such as a photoactiveacid generator. Consequently, when the active component is applied to,especially, a positive resist, a hydrophilic group such as a hydroxylgroup and a carboxyl group is caused (generated) and dissolution by adeveloper is accelerated in an exposed area, and dissolution can berestrained by enhancing an affinity to a base resin by an action of theprotective group (especially a hydrophobic protective group) in anon-exposed area, resulting in enlarging the difference in dissolutionrate between the exposed area and the non-exposed area. In particular,use of a hydrophobic group as the protective group, can realize drasticrestraint of solubility in the non-exposed area as well as restraint ofswelling of resist with development, resulting in improvement ofresolution, even when the particle P in the formula (2) is an inorganicfine particle carrier with high hydrophilicity such as a silicasol. Theremoval (elimination) of the protective group mostly occurred inrelation to (in association with) the photosensitizer, especially bycatalytic action of an acid. As such an acid, an acid generated by lightexposure (especially an acid generated from a photoactive acid generatorconstituting a photosensitive resin composition) is advantageouslyutilized.

[Photosensitive Resin Composition]

Although the photosensitive resin composition (or a resist composition)of the present invention may comprise a photosensitizer and theabove-mentioned active component, usually it comprises a base resin (anoligomer or a polymer), a photosensitizer and the above-mentioned activecomponent. The photosensitive resin composition can be developed by anorganic solvent (e.g., an alcohol), but usually the photosensitive resinis preferred to be capable of water- or alkali-development. A positivephotosensitive resin composition which can be developed by water or analkali aqueous solution is especially preferable.

As the base resin, there may be exemplified a polymer having a polargroup, for example, a hydroxyl group-containing polymer [e.g., apolyvinyl acetal, a polyvinyl alcohol, an ethylene-vinylalcoholcopolymer, a hydroxyl group-containing cellulose derivative (e.g., ahydroxyethyl cellulose), a polyvinyl phenolic resin and a novolak resin(e.g., a phenol novolak resin)], a carboxyl group-containing polymer[e.g., a homo- or copolymer comprising a polymerizable unsaturatedcarboxylic acid (e.g., a (meth)acrylic acid, maleic anhydride anditaconic acid) and a carboxyl group-containing cellulose derivative(e.g., a carboxyl methylcellulose or its salt)], an estergroup-containing polymer [e.g., a homo- or copolymer of a monomer suchas a vinylester of carboxylic acid (e.g., a vinyl acetate) and an esterof (meth)acrylic acid (e.g., a methyl methacrylate) (e.g., a polyvinylacetate, an ethylene-vinyl acetate copolymer and a (meth)acrylic resin)and a polyester, a cellulose ester, etc.], a ether group-containingpolymer [e.g., a polyalkylene oxide, a polyoxyalkylene glycol, apolyvinyl ether-series resin, a silicon-containing resin, a celluloseether, etc.], a carbonate group-containing polymer, an amide orN-substituted amide group-containing polymer [e.g., a polyvinylpyrrolidone, a polyurethane-series polymer, a polyurea, a nylon or apolyamide-series polymer [e.g., a polyamide using a lactam component, adicarboxylic acid component or a diamine component (e.g., nylon 66,nylon 6, a modified nylon, a star-burst dendrimer (D. A. Tomalia. etal., Polymer Journal, 17,117 (1985)), etc.); apoly(meth)acrylamide-series polymer; a polyamino acid; a polymer havinga biuret bond; a polymer having an allophanate bond; and a protein suchas gelatin], a polymer having a nitrile group (e.g., anacrylonitrile-series polymer), a polymer having a glycidyl group (anepoxy resin, a homo- or copolymer of glycidyl(meth)acrylate, etc.), ahalogen-containing polymer (e.g., a polyvinyl chloride, a vinylchloride-vinyl acetate copolymer, a vinylidene chloride-series polymerand a chlorinated polypropylene), a polymerizable oligomer or polymer(e.g., an oligomer or polymer having a polymerizable group such as a(meth)acryloyl group, an allyl group, a vinyl group and a cinnamoylgroup), and the like. The base resin may be utilized either singly or incombination of two or more species.

Incidentally, to enhance the sensitivity against exposure beams of ashorter wavelength, a resin having high transparency to the exposurebeam (e.g., a non-aromatic resin such as a alicyclic resin) may beutilized as the base resin. In the case using the non-aromaticphotosensitive resin (composition), utilization of exposure sources ofshorter wavelength can be achieved as well as formation (orconstitution) of minuter patterns.

As the polymerizable oligomer or resin constituting a negative resist,there may be usually exemplified an epoxy(meth)acrylate, apolyester(meth)acrylate, an unsaturated polyester resin, apolyurethane(meth)acrylate, a polymerizable polyvinyl alcohol-seriespolymer (e.g., a product in a reaction of a polyvinyl alcohol with anN-methylol acrylamide), and the like. The non-polymerizable resinconstituting a negative resist includes a polyvinylphenol-series resin(e.g., a homopolymer of a vinylphenol, a copolymer of a vinylphenol withother copolymerizable monomer(s)), a polyamide-series polymer, asilicone resin-based polymer (a silicone resinous polymer), and thelike. As the copolymerizable monomer, there may be exemplified, forexample, an acrylic monomer (a (meth)acrylic acid, aC₁₋₄alkyl(meth)acrylate such as methyl methacrylate, ahydroxyC₂₋₄alkyl(meth)acrylate such as hydroxyethyl methacrylate, aglycidyl(meth)acrylate), a styrenic monomer such as styrene, and thelike.

In the negative resist, if necessary, a polymerizable monomer oroligomer having a photopolymerizable group (e.g., a (meth)acryloylgroup, an acrylamide group and a vinyl group) [e.g., a monofunctionalphotopolymerizable compound such as a (meth)acrylic acid or a derivativethereof (e.g., a (meth)acrylate and a (meth)acrylamide), vinyl acetate,styrene and N-vinyl pyrrolidone; a polyfunctional (multifunctional)photopolymerizable compound such as a (meth)acrylate of polyol (e.g., anethylene glycol di(meth)acrylate, etc.); and the like] may be usedtogether.

As a photosensitizer in the negative resist, a conventionalphotosensitizer or photo-sensitizer may be employed, for example, anazide compound (e.g., an aromatic azide compound, especially an aromaticdiazide compound), a photoactive acid generator (e.g., an ester ofsulfonic acid, a salt of a Lewis acid, etc.) and a crosslinking agent(e.g., a melamine derivative such as a methylol melamine and aalkoxymethylmelamine, etc.), a pyrylium salt, a thiapyrylium salt, aphotodimerization sensitizer, a photopolymerization initiator [a ketone(acetophenone, propiophenone, an anthraquinone, a thioxanthone,benzophenone or a derivative thereof), a benzoin ether or a derivativethereof, an acylphosphineoxide, etc.], a dissolution inhibitor, and thelike.

The preferred negative resists include a combination of a resin having aphenolic hydroxyl group (e.g., a novolak resin and a polyvinyl phenolicresin), a photoactive acid generator, and a crosslinking agent, and thelike.

The typical base resin constituting a positive resist includes a novolakresin (e.g., a phenol novolak resin), a resin in which a hydrophilicgroup (e.g., a hydroxyl group and/or a carboxyl group) is protected by aprotective group capable of removing (removable) [e.g., a polyvinylphenolic resin in which a phenolic hydroxyl group is protected by aprotective group capable of removing (removable) (e.g., a homopolymer ofa vinylphenol, or a copolymer of a vinylphenol and the above-exemplifiedcopolymerizable monomer, etc.), a hydroxyl and/or carboxylgroup-containing (meth)acrylic resin (e.g., a homo- or copolymer of(meth)acrylate, or a copolymer of (meth)acrylate and theabove-exemplified copolymerizable monomer), a hydroxyl and/or carboxylgroup-containing cyclic olefinic resin, etc.] and the like.

The preferred base resin is a homo- or copolymer of a monomer forming ahydrophilic group (an alkali-soluble group or a group which impartsalkali-solubility) by catalytic action of an acid (especially an acidgenerated from an acid generator), for example, a homo- or copolymer ofa vinyl-series monomer such as a polyvinyl phenolic resin; a homo- orcopolymer of a vinyl-series or (meth)acrylic monomer having a monocyclicalicyclic hydrocarbon group, a homo- or copolymer of a vinyl-series or(meth)acrylic monomer having a crosslinked cyclic hydrocarbon group(such as a norbornyl group and an adamantyl group); a homo- or copolymerof a cyclic olefin [e.g., a homopolymer of a C₅₋₈cyclic monoolefin suchas cyclopentene, a crosslinked or terpene-series C₇₋₁₂cyclic monoolefinsuch as norbornene and bornene, a cyclic diene such as cyclopentadieneand dicyclopentadiene or a copolymer with a copolymerizable monomer(e.g., the above-mentioned monomers, besides maleic anhydride, etc.)];and the like. In these polymers, the hydrophilic groups such as hydroxylgroups and carboxyl groups are usually protected by a protective grouppartially or wholly. The proportion of the protective group relative tothe hydrophilic group of the base resin may be about 10 to 100 mol %,preferably about 20 to 100 mol %, and more preferably about 30 to 100mol %.

Incidentally, the above-mentioned resin forming a hydrophilic group bydeprotection may be obtained by polymerizing a monomer in which ahydrophilic group is protected by a protective group (e.g., theprotective group exemplified in the section of the active alkoxide) inadvance, or may be obtained by polymerizing a monomer having ahydrophilic group and protecting the hydrophilic group of the obtainedresin by the protective group.

Among the monomers having a hydrophilic group, as a monomer having ahydroxyl group, such a polymerizable monomer having one or pluralhydroxyl group(s) is mentioned, for example, a cyclic olefin (e.g., amonocyclic or a crosslinked cyclic olefin such as a hydroxycyclohexeneand a hydroxynorbornene); a vinylphenolic monomer (e.g., ahydroxystyrene and a hydroxyvinyltoluene); a hydroxyalkyl(meth)acrylate(e.g., hydroxyC₂₋₄alkyl(meth)acrylate such ashydroxyethyl(meth)acrylate, hydroxypropyl(meth)acrylate and2-hydroxybutyl(meth)acrylate, etc.); a vinyl monomer having a monocyclicalicyclic group such as a vinylhydroxycyclohexane, a (meth)acrylatehaving a monocyclic alicyclic group [e.g., ahydroxycycloalkyl(meth)acrylate (e.g., ahydroxycycloC₅₋₈alkyl(meth)acrylate, etc.) such as ahydroxyhexyl(meth)acrylate, a hydroxyoxacycloalkyl(meth)acrylate, etc.];a (meth)acrylate having a crosslinked alicyclic group such as ahydroxynorbornyl (meth)acrylate and a hydroxyadamantyl(meth)acrylate(e.g., a hydroxybi- or tri-C₇₋₂₀cycloalkyl(meth)acrylate); a C₅₋₈cyclicmonoolefin such as a hydroxycyclopentene, a bridged cyclic orterpene-series C₇₋₁₂alkcyclic olefin such as a hydroxynorbornene and ahydroxybornene, a cyclic diene such as a hydroxycyclopentadiene and ahydroxydicyclopentadiene; and the like. These monomers having a hydroxylgroup can be used either singly or in combination.

As a monomer having a carboxyl group, there may be mentioned apolymerizable monomer having one or plural carboxyl group(s) or one orplural acid anhydride group(s), for example, a (meth)acrylic acid,maleic acid, fumaric acid, maleic anhydride, itaconic acid, avinylbenzoic acid, a (meth)acrylate having a monocyclic alicyclic groupsuch as a carboxycycloalkyl (meth)acrylate (e.g., acarboxycycloC₅₋₈alkyl(meth)acrylate; a (meth)acrylate having acrosslinked alicyclic group (e.g., a carboxybi- ortri-C₇₋₂₀cycloalkyl(meth)acrylate) such as acarboxynorbornyl(meth)acrylate and a carboxyadamantyl (meth)acrylate; aC₅₋₈cyclic monoolefin such as a carboxycyclopentene, a bridged cyclic orterpene-series C₇₋₁₂cyclic olefin such as a carboxynorbornene and acarboxybornene, a cyclic diene such as a carboxycyclopentadiene and acarboxydicyclopentadiene and the like. These monomers having a carboxylgroup can be used either singly or in combination.

These monomers having a hydrophilic group may be used in a combinationof monomers having different kind of hydrophilic groups, for example, acombination of a monomer having a hydroxyl group with a monomer having acarboxyl group. Further, a monomer having a hydrophilic group may beused in combination with a copolymerizable monomer.

As the copolymerizable monomer, there may be exemplified, for example,an alkyl(meth)acrylate; a glycidyl(meth)acrylate; a styrenic monomersuch as styrene; a (meth)acrylate having a monocyclic alicyclic groupsuch as a cycloalkyl(meth)acrylate and an oxacycloalkyl(meth)acrylate; a(meth)acrylate having a crosslinked alicyclic group such as anorbornyl(meth)acrylate and an adamantyl(meth)acrylate. Thecopolymerizable monomer can be used either singly or in combination. Inthe copolymer with a copolymerizable monomer, the proportion of themonomer having a hydrophilic group is, relative to the total amount ofmonomers, about 10 to 100% by weight, preferably about 25 to 80% byweight, and more preferably about 30 to 70% by weight.

In the resin forming a hydrophilic group by deprotection, as aprotective group for the hydrophilic group, there may be mentioned theprotective groups exemplified in the section of the active metalalkoxide, for example, a protective group for a hydroxyl group such asan alkoxyalkyl group, an alkoxycarbonyl group, a cycloalkyl group, anoxacycloalkyl group and a crosslinked alicyclic group; and a protectivegroup for a carboxyl group such as an alkyl group.

The typical resin includes, for example, a resin (e.g., a vinyl phenol,a homo- or copolymer of a hydroxyl group-containingalicyclic(meth)acrylate such as a hydroxycycloalkyl(meth)acrylate, ahydroxynorbornyl(meth)acrylate and a hydroxyadamantyl(meth)acrylate, ahomo- or copolymer of a cyclic olefin such as a hydroxynorbornene and ahydroxycyclopentadiene) in which a hydroxyl group is protected by aprotective group such as an alkoxyalkyl group, an alkoxycarbonyl group(t-BOC group, etc.) and an acetal group; a (meth)acrylic resin (e.g., ahomo- or copolymer of a hydroxyalkyl(meth)acrylate, etc.) in which ahydroxyl group is protected by an alicyclic group such as a cycloalkylgroup (including an oxacycloalkyl group and a bi- or tricycloalkyl groupsuch as norbornyl group and adamantyl group); a (meth)acrylic resin(e.g., a homo- or copolymer of an unsaturated carboxylic acid or an acidanhydride thereof such as (meth)acrylic acid and maleic anhydride, ahomo- or copolymer of a carboxyl group-containingalicyclic(meth)acrylate such as a carboxynorbornyl(meth)acrylate and acarboxyadamantyl(meth)acrylate, a homo- or copolymer of a cyclic olefinsuch as a carboxynorbornene and a carboxycyclopentadiene) in which acarboxyl group is protected by a protective group such as an alkyl group(e.g., t-butyl group).

The preferred positive resist includes a combination of a phenol novolakresin and a photosensitizer (e.g., a quinonediazide such as adiazobenzoquinone derivative and a diazonaphthoquinone derivative,etc.), and a combination between a resin forming a hydrophilic group bya deprotection (especially deprotection by catalytic action of an acidgenerated from an acid generator) and a photosensitizer (photoactiveacid generator).

Further, the base resin may have various functional groups, for example,a hydroxyl group, an alkoxy group, a carboxyl group, an acid anhydridegroup, an alkoxycarbonyl group, an acyl group and an amino group, inaddition to the above-mentioned hydrophilic group.

As a photosensitizer in the positive resist, a conventionalphotosensitizer or photo-sensitizer may be selected from, for example, adiazonium salt (e.g., a diazonium salt, a tetrazonium salt, apolyazonium salt, etc.), a quinonediazide (e.g., a diazobenzoquinonederivative and a diazonaphthoquinone derivative), a photoactive acidgenerator and a dissolution inhibitor.

As the photoactive acid generator, there may be exemplified thefollowing compounds. Incidentally, trade names produced by Midori KagakuCo. Ltd. are written within parentheses for reference. As thephotoactive acid generator, there may be exemplified a derivative ofsulfonium salt [e.g., a sulfonic acid ester (e.g., an arylalkanesulfonate (particularly, a C₆₋₁₀arylC₁₋₂alkane sulfonate) such as1,2,3-tri(methylsulfonyloxy)benzene); an arylbenzene phosphonate(particularly, a C₆₋₁₀aryltoluene phosphonate which may have a benzoylgroup) such as 2,6-dinitrobenzyltoluenesulfonate and a benzoin tosylate;an aralkylbenzene sulfonate (particularly, a C₆₋₁₀aryl-C₁₋₄alkyltoluenesulfonate which may have a benzoyl group) such as2-benzoyl-2-hydroxy-2-phenylethyltoluene sulfoonate; a disulfone such asa diphenylsulfone; a Lewis acid salt (e.g., a triarylsulfonium salt(particularly, a triphenylsulfonium salt) such as a triphenylsulfoniumhexafluorophosphate (TPS-102), a triphenylsulfonium hexafluoroantimony(TPS-103), 4-(phenylthio)phenyldiphenylsulfonium hexafluoroantimony(DTS-103), 4-methoxyphenyldiphenylsulfonium hexafluoroantimony(MDS-103), a triphenylsulfonium methanesulfonyl, a triphenylsulfoniumtrifluoromethanesulfonyl (TPS-105) and a triphenylsulfoniumnonafluorobutanesulfonyl (TPS-109), etc.], a derivative of phosphoniumsalt; a derivative of diarylhalonium salt [e.g., a Lewis acid salt suchas a diaryliodonium salt (e.g., diphenyliodoniumhexafluorophosphate,4,4′-di(t-butylphenyl)iodonium hexafluorophosphate (BBI-102),4,4′-di(t-butylphenyl)iodonium hexafluoroantimonate (BBI-103),4,4′-di(t-butylphenyl)iodonium tetrafluoroborate (BBI-101),4,4′-di(t-butylphenyl)iodonium trifluoromethanesulfonate (BBI-105),4,4′-di(t-butylphenyl)iodonium camphorsulfonate (BBI-1060),diphehyliodonium trifluoromethanesulfonate (DPI-105), 4-methoxyphenylphenyliodonium trifluoromethanesulfonate (DPI-105), etc.), a derivativeof a diazonium salt (a Lewis acid salt such asp-nitrophenyldiazoniumhexafluorophosphate), a diazomethane derivative, atriazine derivative [e.g., a haloalkyltriazinylaryl such as1-methoxy-4-(3,5-di(trichloromethyl)triazinyl)naphthalene (TAZ-106) and1-methoxy-4-(3,5-di(trichloromethyl)triazinyl)benzene (TAZ-104), ahaloalkyltriazinylalkenylaryl such as1-methoxy-4-[2-(3,5-ditrichloromethyltriazinyl)ethenyl]benzene(TAZ-110),1,2-dimethoxy-4-[2-(3,5-ditrichloromethyltriazinyl)ethenyl]benzene(TAZ-113) and1-methoxy-2-[2-(3,5-ditrichloromethyltriazinyl)ethenyl]benzene(TAZ-118), etc.], an imidylsulfonate derivative [a succinimidylcamphorsulfonate (SI-106), succinimidyl phenylsulfonate (SI-100),succinimidyl toluylsulfonate (SI-101), succinimidyltrifluoromethylsulfonate (SI-105), phthalimidyl trifluorosulfonate(PI-105), naphthalimidyl camphorsulfonate (NAI-106), naphthalimidylmethanesulfonate (NAI-100), naphthalimidyl tuluylsulfonate (NAI-101),norborneneimidyl trifluoromethanesulfonate (NDI-105), etc.], and thelike. Moreover, sulfone derivatives are also included, for example, acompound having a unit —SO₂—C(═N)— such as trade name “DAM-101”,“DAM-102”, “DAM-105” and “DAM-201”; a compound having a unit —CH₂SO₂—such as “DSM-301”; a compound having a unit ═N—O—SO₂— such as “PAI-101”.Particularly, Lewis acid salts (e.g., Lewis acid salts such asphosphonium salts) are preferred.

In the negative and positive resists, the amount to be used of thephotosensitizer can be selected, for example, from the range of about0.1 to 50 parts by weight, preferably about 1 to 30 parts by weight, andmore preferably about 1 to 20 parts by weight (especially about 1 to 10parts by weight), relative to 100 parts by weight of a base resin.

Incidentally, the photosensitive resin (composition) can be selectedaccording to exposing wavelength, too, for example, in the case of usingKrF excimer laser (248 nm) as a light source for exposure, there can beused, for example, a chemical-amplifying positive photosensitive resincomposition which comprises a vinyl-series resin (e.g., a polyvinylphenol resin in which a hydroxyl group is protected by a leaving group)or an acrylic polymer (e.g., a (meth)acrylic homo- or copolymer in whicha carboxyl group is protected by a leaving group) and a photosensitizer(e.g., an acid generator), and a dissolution inhibitor.

In the case of using ArF excimer laser (193 nm) as the light source forexposure, there can be used, for example, a chemical-amplifying positivephotosensitive resin composition which comprises a (meth)acrylic resin(e.g., an aliphatic group-containing (meth)acrylic homo- or copolymer inwhich a carboxyl group is protected by a protective group (a leavinggroup) such as t-butyl group and an alicyclic hydrocarbon group (e.g.,an adamantyl group, etc.) or a resin (a homo- or copolymer) containingan alicyclic hydrocarbon such as norbornene in the main chain, aphotosensitizer (an acid generator), a dissolution inhibitor, and thelike.

Moreover, in the case of using F₂ excimer laser (157 nm) as a lightsource for exposure, there can be used, for example, achemical-amplifying positive photosensitive resin composition whichcomprises a polymer having a carbon-fluorine bond or a silicon-oxygenbond, or a homo- or copolymer of a phenolic monomer, a photosensitizer(an acid generator), a dissolution inhibitor, and the like.

In the photosensitive resin composition of the present invention, theamount of the active component can be selected from the wide range ofabout 0.01 to 1000 parts by weight as far as film-formability,sensitivity, resolution of patterns are not damaged, and is usuallyselected from the range of about 5 to 1000 parts by weight, preferablyabout 10 to 500 parts by weight and more preferably about 10 to 300parts by weight, especially about 10 to 100 parts by weight, on a solidmatter basis, relative to 100 parts by weight of a base resin.

To the photosensitive resin composition, various additives may be added,for example, a stabilizer (e.g., an antioxidant), a plasticizer, asurfactant, a dissolution accelerator, and a coloring agent (e.g., dyes,pigments), if necessary. Further, for ease of handling, for example, inorder to improve handling properties such as coating, the photosensitiveresin composition may comprise a solvent (e.g., the solvents exemplifiedin the section of the active metal alkoxide).

The photosensitive resin composition of the present invention can beprepared in accordance with a conventional method, for example, bymixing a photosensitive resin [a photosensitive resin compositioncomprising a base resin (a polymer or an oligomer) and aphotosensitizer] and an active component. The photosensitive resincomposition usually contains a solvent [e.g., the solvents exemplifiedin the section of the active metal alkoxide (e.g., a hydrophilic orwater-soluble solvent), for example, an ester of lactic acid such asethyl lactate; an alkylene glycol alkylether acetate such as ethyleneglycol alkylether acetate and propylene glycol methylether acetate(e.g., PGMEA); a (poly)oxyalkylene glycol alkylether acetate].

[Photosensitive Layer]

The photosensitive layer can be formed by applying (spreading orcoating) the above-described photosensitive resin composition to asubstrate (a base material). According to the intended pattern and use,the substrate can be suitably selected from metals (aluminum), glass,ceramics (e.g., alumina, copper doped alumina and tungsten silicate),plastics and others, and the substrate may be a semiconductor substratesuch as silicon wafer.

The surface of the substrate may be previously treated thereby toimprove the adhesion with the photosensitive layer, depending on itsintended use. The surface treatment includes a surface treatment usingthe silane coupling agent described above (e.g., a hydrolyticpolymerizable silane coupling agent having a polymerizable group) orothers, a coating treatment with an anchor coating agent or a base coatagent (e.g., a polyvinyl acetal, an acrylic resin, a vinylacetate-series resin, an epoxy resin, a urethane resin), or with amixture of such base coat agent with an inorganic fine particles(particles finely divided), and others.

Incidentally, after applying the photosensitive resin composition to thesubstrate, solvents may be evaporated by drying. For example, removal ofsolvents may be conducted by soft-baking (pre-baking) with the use of aheating means such as a hot plate.

So that the photosensitive resin composition of the present inventioncan improve plasma resistance (oxygen plasma resistance), heatresistance and dry etching resistance, too, it is preferred that thephotosensitive layer is formed at least on the surface of a resistlayer. The structure of the photosensitive layer can be selectedaccording to the process of forming patterns or the intended circuitstructures, and may be a single- or multi-layered structure (or alamination layer, a composite structure). For example, a single-layeredphotosensitive layer is utilized in a single-layer forming process inwhich a single photosensitive layer is formed on a substrate, andparticularly suitable for use in forming a heat-resistant pattern by dryetching. A multi-layered (composite structure) photosensitive layerimproves the oxygen plasma resistance largely, and thus it isadvantageous in improving the resolution even when the exposingwavelength (of light) for irradiation is at the vicinity of limit oflithography resolution. For example, a double-layered photosensitivelayer is utilized in a double-layer forming process comprising: formingan undercoat resist layer (which does not necessarily havephotosensitivity) on a substrate, forming a photosensitive layerthereon, exposing the photosensitive layer to light, developing thepattern, and etching the undercoat resist layer to give a pattern byplasma treatment (e.g., oxygen plasma treatment, etc.) or other means. Atriple-layered photosensitive layer can be utilized in a multi-layerforming process in which an undercoat layer, an intermediate layer and aphotosensitive layer are formed on a substrate in this order, exposed tolight and patterned by developing, and then the intermediate andundercoat layers are etched. The undercoat and intermediate layers maybe made from compositions composed of any photosensitive resins (e.g., aphotosensitive resin composition comprising a base resin and aphotosensitizer) and inorganic fine particles, or from photosensitiveresins containing no inorganic fine particle (e.g., a photosensitiveresin composition comprising a base resin and a photosensitizer).

The thickness of the photosensitive layer is not particularly restrictedand, for example, can be selected within the range of about 0.01 to 10μm, preferably about 0.05 to 5 μm, preferably about 0.08 to 2 μm, and isusually about 0.09 to 1 μm (e.g., about 0.1 to 0.7 μm).

The photosensitive layer can be formed by conventional coating methodssuch as spin coating method, dipping method, and casting method. Ifnecessary, the coated composition is dried to remove the solvent therebyto form a photosensitive layer.

[Process for Forming Pattern]

Patterns (particularly, minute patterns) can be carried out by aconventional lithography technique which is a combination of exposure,development and etching.

For example, a pattern can be formed by applying or coating thephotosensitive resin composition onto a substrate to form aphotosensitive layer, exposing the coating layer to light, anddeveloping the light-exposed layer. In particular, in the case using achemical-amplifying photosensitive resin, heating treatment ispreferably conducted after exposure (e.g., baking after exposure (postexposure bake, PEB)), to efficiently diffuse an acid generated byexposure. Moreover, after patterning by development, an etchingtreatment by plasma treatment (e.g., oxygen plasma) may be conducted.

The exposure of the photosensitive layer can be carried out according toa conventional method, for example, by pattern-irradiating the layerwith light or pattern-exposing the layer to light, through a given mask.As the light for patternwise exposure, various beams (e.g., a beam ofwavelengths of about 50 to 450 nm, especially about 100 to 450 nm) areavailable, for example, a beam of a halogen lamp, a high pressuremercury lamp, a UV lamp and others; a radial ray (radiation ray) of anexcimer laser [e.g., XeCl (308 nm), KrF (248 nm), KrCl (222 nm), ArF(193 nm), ArCl (172 nm) and F2 (157 nm)], an electron beam (g-ray (436nm), i-ray (365 nm), etc.), X-ray and EB-ray, depending on thephotosensitive properties of the photosensitive resin composition, thedegree of minuteness of the pattern, kinds of the base resin and so on,and the beams may be the ones of single-wavelength or complex(composite)-wavelength. In particular, the excimer lasers such as KrF(248 nm), ArF (193 nm) and F₂ (157 nm) are advantageously utilized.Moreover, with the use of resists comprising a non-aromatic base resin,transparency against shorter wavelength beams can be realized as well asimprovement of sensitivity. For example, in the case of using KrFexcimer laser (248 nm) as the light source for exposure, such achemical-amplifying photosensitive resin composition is available, forexample, a positive photosensitive resin composition which comprises aresin forming a hydrophilic group by deprotection [e.g., a polyvinylphenolic resin in which a hydroxyl group is protected by a protectivegroup or a (meth)acrylic resin in which a carboxyl group is protected bya protective group] and a photosensitizer (acid generator); and anegative photosensitive resin composition which comprises theabove-mentioned resin forming a hydrophilic group by deprotection, anacid generator and a crosslinking agent; and others.

Incidentally, the energy for exposure can be selected according to thephotosensitive properties (e.g., solubility, etc.) of the abovephotosensitive resin composition, and the exposing time can be usuallyselected within the range of about 0.005 second to 10 minutes, andpreferably about 0.01 second to 1 minute.

After exposure, heat treatment may be conducted, if necessary. Inparticular, in the case of using a chemical-amplifying photosensitiveresin composition, heat treatment (PEB) is advantageously conducted. Thetemperature of heating (pre-bake and PEB) is about 50 to 150° C.,preferably about 60 to 150° C., more preferably about 70 to 150° C., andheating time is about 30 seconds to 5 minutes, preferably about 1 to 2minutes.

The high resolution pattern can be formed by developing thephotosensitive layer in a conventional manner after pattern-exposing.Various developers or developing agents (e.g., water, alkaline aqueoussolutions) are usable for development, and the choice thereof depends onthe type of the photosensitive resin composition. Preferred developersinclude water and alkaline developers. If necessary, the developer maycontain a small amount of an organic solvent (e.g., a hydrophilic orwater-soluble solvent such as alcohols typified by methanol, ethanol,and isopropanol, ketones typified by acetone, ethers typified bydioxanes and tetrahydrofurane, cellosolves, cellosolve acetates), asurfactant and others. There is no particular restriction on thedeveloping method, and the paddle (meniscus) method, dipping method,spraying method and others are adaptable.

Incidentally, besides the pre-bake and PEB, in an appropriate step fromapplication of the photosensitive resin composition to development, thecoated film (photosensitive layer) may be subjected to heat- orcure-treatment at a suitable temperature. If necessary, for example,after the development, the coated film may be subjected toheat-treatment.

In the present invention, introduction of a functional group whichcauses a difference in solubility by light exposure, into an activecomponent can achieve causing the difference in solubility betweenexposed area and non-exposed area, even if the active component iscombined with a photosensitive resin (a photosensitive resin compositioncomprising a base resin and a photosensitizer) to form a photosensitivelayer. In particular, when the group causing the difference insolubility is a hydrophilic group protected by a protective group, sincethe formed photosensitive layer is protected (especially becomeshydrophobic) and the surface of the layer becomes hydrophobic state,especially in a positive resist, hydrophobic state in a non-exposed areacan be maintained, resulting in deprotecting of the protecting group andaccelerating dissolution in the exposed area. Thus, difference indissolution rate between non-exposed area and exposed area larger can beenlarged. Moreover improving edge roughness can be realized, as well asobtaining an edge being a sharp pattern in a plane shape and in a shapeat cross section.

Incidentally, various hypotheses are proposed as a cause of the edgeroughness, and part of the reason for the cause are said to be thefollowing factors, nonuniformity of resist composition in a pattern-edgepart, aggregation between a hydrophobic polymer (in the case of positivechemical-amplifying resist, a polymer before deprotection) and ahydrophilic polymer, nonuniform dispersal of a photoactive acidgenerator in a resist, and others.

INDUSTRIAL APPLICABILITY

According to the present invention, introduction of a group which causesa difference in solubility by light exposure, into an active componentcan be enlarged the difference in solubility between exposed area andnon-exposed area, even if the active component is combined with aphotosensitive resin (a photosensitive resin composition comprising abase resin and a photosensitizer) to form a photosensitive layer,resulting in forming a pattern with high sensitivity and highresolution. In particular, when an active component comprises a specificactive metal alkoxide or a polycondensate thereof, contamination ofimpurity can be efficiently inhibited (avoided). Further, according tothe photosensitive resin composition of the present invention, withkeeping etching resistance against oxygen plasma, edge roughness of thepattern can be largely improved, furthermore, high sensitivity for alight source of shorter wavelength light source can be achieved,resulting in improving resolution of patterns to a large extent.

Therefore, the present invention can be utilized in a variety ofapplication such as a material for forming circuits (a resist forsemiconductor production, a printed wiring board, etc.), a material forforming image (a printing plate material, a materials for reliefprinting, etc.). In particular, the present invention can beadvantageously utilized in the resist for semiconductor productionbecause high sensitivity and high resolution can be achieved.

EXAMPLES

Hereinafter, the present invention will be described in further detailbased on examples, and the examples should by no means be construed asdefining the scope of the invention.

Examples 1 to 2 and Comparative Example 1

1. Preparation of a Photosensitive Resin Composition

(1) Preparation of a Photosensitive Resin

To 1 part by weight of polyvinylphenol resin having a weight averagemolecular weight of 8,500 in which 37 mol % of the hydroxyl group wassubstituted with t-BOC (tert-butoxycarbonyloxy) group, was added 0.02part by weight of the photoactive acid generator represented by thefollowing formula (A), and to the resultant mixture, 6 parts by weightof propylene glycol monomethyl ether acetate as a solvent were added andmixed to prepare a positive photoresist.

(2) Active Component (Silicasol)

(i) Synthesis of 1-(t-butoxycarbonyoxy)-4-iodobenzene

Into 1250 mL of acetone, were dissolved 125.0 g (568 mmol) ofp-iodophenol and 69 mg (5.7 mmol) of N,N-dimethylaminopyridine, and tothus obtained solution, 124 g (568 mmol) of di-t-butylcarbonate wasadded dropwise at 40° C. with stirring. After completion of dropping,the reaction solution was kept with stirring for one night to carry outthe reaction. After completion of the reaction, the obtained solutionwas put into 5 L of iced water. The formed precipitation was collectedby suction filtration, dried and recrystallized by methanol to provide113 g of 1-(t-butoxycarbonyoxy)-4-iodobenzene.

(ii) Synthesis of1-[2-{(3-trimethoxysilyl)propyloxycarbonyl}vinyl]-4-(t-butoxycarbonyloxy)benzene

Into a mixture of 1 L of triethylamine and 200 mL of acetonitrile, weredissolved 55.0 g of 1-(t-butoxycarbonyloxy)-4-iodobenzene synthesized inthe step (i) and 42.5 g of 3-trimethoxysilylpropyl acrylate, and thereaction system was substituted by argon by bubbling argon into liquidphase. To the reaction system, was added 770.0 mg of palladium acetateas a catalyst, the mixture was refluxed for one night (Hech reaction).After completion of the reaction, removing the solvent, a product wasextracted by hexane from obtained residue. Hexane was removed from theextraction to prepare 47.5 g of3-(trimethyxysilyl)propylp-(t-butoxycarbonyloxy)cinnamate, that is,1-[2-{(3-trimethoxysilyl)propyloxycarbonyl}vinyl]-4-(t-butoxycarbonyloxy)benzenebeing the objective compound.

The formula of the reaction steps including the above-mentioned step isshown as follows:

The ¹H-NMR and IR spectra of the obtained compound are shown in FIG. 1and FIG. 2, respectively.

¹H-NMR(CDCl₃) ppm: 0.7(t, 2H, CH₂), 1.6(s, 9H, t-Bu), 1.8(q, 2H, CH₂),3.6(s, 9H, OCH₃), 4.2(t, 2H, CH₂), 6.4(d, 1H, C═CH), 7.2(d, 2H, C₆H₄),7.5(d, 2H, C₆H₄), 7.6(d, 1H, C═CH).

Moreover, in FIG. 2, absorption by C═O stretching vibration in estergroups and carbonate groups was observed in the vicinity of 1700 to 1800cm⁻¹. It is obvious that the objective compound is obtained from theseresults.

(iii) Synthesis of a Silicasol

Into a 300 mL of reactor, were fed 70 g of propylene glycolmonomethylether acetate (PGMEA) and 54 g of 20% by weight aqueousammonia, and the mixture was stirred at 30° C. for 20 minutes. Into theresultant solution, 22.1 g of1-[2-{(3-trimethoxysilyl)propyloxycarbonyl}vinyl]-4-(t-butoxycarbonyloxy)benzenesynthesized in the step (ii), 2.34 g of tetraethoxysilane and 2.0 g oftriethoxymethylsilane were respectively added dropwise for 1 hour, andfurther stirred at 30° C. for 6 hours. Thereafter, the reaction solutionwas filtered by a membrane filter having a mean hole size of 0.1 μm, andthen ammonia was removed by rinsing the filtrate with purified water,and further water was removed by dehydration under a reduced pressure.After that, the content of propylene glycol monomethylether acetate(PGMEA) was adjusted by addition, or removal under a reduced pressure toprepare a propylene glycol monomethylether acetate (PGMEA) solution ofsilicasol in which the content of silicasol is 30% by weight.

(3) Preparation of a Photosensitive Resin Composition

The photosensitive resin obtained in the step (1) and the activecomponent (silicasol) obtained in the step (2) were mixed together inthe ratio shown in Table 1 (denoted by solid ratio without solvent) toprepare a photosensitive resin composition. Incidentally, the examplewithout the active component (silicasol) was made as Comparative Example1.

2. Pattern Formation and Evaluation of Properties (Sensitivity,Resolution and Oxygen Plasma Resistance)

(1) Pattern Formation

After treating a washed silicon wafer by hexamethyldisilazane, thephotosensitive resin composition was coated on the wafer by means of aspin coater in order that a resist layer of 0.4 μm thick after dried wasformed and the wafer was baked on a hot plate at 100° C. for 1 minute.Thereafter, exposure was conducted through a test mask having aline-and-space pattern with different line widths, using a reducedprojection exposing machine (manufactured by Canon Inc., FPA-3000EX5,NA=0.63) having an exposing wavelength of 248 nm (KrF excimer laser)with the exposure amount varied in steps. After baking the wafer at 100°C. on a hot plate for 1 minute, the wafer was paddle-developed with2.38% by weight a tetramethylammonium hydroxide aqueous solution for 1minute to give a positive pattern.

(2) Evaluation of the Properties

The positive pattern was evaluated for its properties according to thefollowing manner.

-   (i) Sensitivity: expressed in terms of such an amount of exposed    dose to print just as the same size of the mask with a line width of    0.25 μm that the ratio of the width of the line relative to that of    the space becomes 1:1 (the smaller the value is, the higher the    sensitivity is).-   (ii) Resolution: expressed in terms of a minimum width of the lines    distinctly formed by exposing at the amount of exposed dose in which    the line width of the mask is 0.25 μm, the ratio of the width of the    line relative to that of the space becomes 1:1 (the smaller the    value is, the higher the resolution is).-   (iii) Oxygen plasma resistance: using a plasma etching device    (manufactured by Tokyo Shinku, K.K., SUPER COAT N400), the wafers    after development were subjected to oxygen plasma etching under the    following conditions.

Feeding system: cathode couple

Electrode size: 80 mmØ

Gas: oxygen

Pressure: 8.645 Pa

rf voltage applied: 85W

rf electric power density: 1.69 W/cm²

Treatment time: 5 minutes

The film thickness of each wafer after etching was measured. Thethickness of the lost portion by etching was divided by etching time togive a value represented by the rate of oxygen plasma (O₂-RIE rate,nm/sec). The smaller the value is, the higher the oxygen plasmaresistance is. The results are shown in Table 1.

TABLE 1 Composition Active Photosensitive component resin (silicasol)O₂-RIE (parts by (parts by Sensitivity Resolution rate weight) weight)(mJ/cm²) (μm) (nm/sec) Ex. 1 1 0.11 30 0.17 45 Ex. 2 1 0.25 25 0.17 20Comp. 1 0 50 0.23 70 Ex. 1 Examples 3 to 4 and Comparative Example 2 1.Preparation of a photosensitive resin composition (1) Preparation of aphotosensitive resin

Into methylisobutylketone, were dissolved 2-methyladamantyl methacrylateand γ-butylolactone methacrylate at the nurture ratio (molar ratio) of1/1, radical polymerization was conducted at 80° C. for 10 hours usingazobisisobutylonitrile (AIBN) as an initiator to prepare a resin havinga weight average molecular weight of 14,500. n-Hexane was used as asolvent for reprecipitation. Into 1 part by weight of the obtainedresin, was added 0.02 part by weight of the photoactive acid generatorrepresented by the following formula (B), and mixed with 7 parts byweight of propylene glycol monomethyl ether acetate as a solvent toprepare a positive photoresist.

(2) Active Component (Silicasol)(i) Synthesis of tert-butyl 3-[3-(trimethoxysilyl)propylthio]propionate

Into 300 mL of dehydrated ethyl acetate, were dissolved 58.8 g (0.3 mol)of 3-(trimethoxysilyl)-1-propanethiol and 38.4 g (0.3 mol) of tert-butylacrylate, and the reaction system was substituted by argon by bubblingargon in thus obtained solution. To the reaction solution, was added2.94 g of dicumylperoxide (manufactured by NOF Corporation ltd.,PERBUTYL PV) as a radical initiator, the mixture was refluxed withheating for 24 hours. After completion of the reaction, solvent wasremoved to prepare 96.0 g (0.294 mol) of tert-butyl3-[3-(trimethoxysilyl)propylthio]propionate being the objectivecompound.

The formula of the reaction steps is shown as follows:

The ¹H-NMR and IR spectra of the obtained compound are shown in FIG. 3and FIG. 4, respectively.

¹H-NMR: 0.7, 1.6-1.8, and 2.4-2.8 ppm: methylene(CH₂) 1.4 ppm:t-butyl(CH₃)₃C 3.6 ppm: methoxy(OCH₃)₃

Moreover, in FIG. 4, specific absorption by carbonyl group was observedin the vicinity of 1730 to 1740 cm⁻¹. It is obvious that objectivecompound is obtained from these results.

(ii) Synthesis of a Silicasol

Into a 300 ml reactor, were fed 70 g of propylene glycol monomethyletheracetate (PGMEA) and 54 g of 20% by weight aqueous ammonia, and thereaction mixture was stirred at 30° C. for 20 minutes. Into theresultant mixture, 42.0 g of tert-butyl3-[3-(trimethoxysilyl)propylthio]propionate synthesized in the step (i),3.1 g of tetraethoxysilane and 2.7 g of triethoxymethylsilane wererespectively added dropwise for 1 hour, and further stirred at 30° C.for 6 hours. Thereafter, the reaction solution was filtered by amembrane filter having mean hole size of 0.1 μm, and then ammonia wasremoved by rinsing the filtrate with purified water, and further waterwas removed by dehydration under a reduced pressure. After that, thecontent of propylene glycol monomethylether acetate (PGMEA) was adjustedby addition or removal under a reduced pressure to prepare a propyleneglycol monomethylether acetate (PGMEA) solution of silicasol in whichcontent of silicasol is 30% by weight.

(3) Preparation of a Photosensitive Resin Composition

The photosensitive resin obtained in the step (1) and the activecomponent (silicasol) obtained in the step (2) were mixed together inthe ratio shown in Table 2 (denoted by solid ratio without solvent) toprepare a photosensitive resin composition. Incidentally, the examplewithout the active component (silicasol) was made as ComparativeExample.

2. Pattern Formation and Evaluation of Properties (Sensitivity,Resolution and Oxygen Plasma Resistance)

(1) Pattern Formation

After treating a washed silicon wafer by hexamethyldisilazane, thephotosensitive resin composition was coated on the wafer by means of aspin coater in order that a resist layer of 0.3 μm thick after dried wasformed, and the wafer was baked on a hot plate at 130° C. for 1 minute.Thereafter, exposure was carried out through a test mask having aline-and-space pattern with different line widths, using a reducedprojection exposing machine (NA=0.63) having an exposing wavelength of193 nm (ArF excimer laser) with the exposure amount varied in steps.After baking the wafer at 130° C. on a hot plate for 1 minute, the waferwas paddle-developed with 2.38% by weight a tetramethylammoniumhydroxide aqueous solution for 1 minute to give a positive pattern.

(2) Evaluation of Properties of Resist

The positive pattern was evaluated for its properties according to thefollowing manner.

-   (i) Sensitivity: expressed in terms of such an amount of exposed    dose to print just as the same size of the mask with a line width of    0.20 μm that the ratio of the width of the line relative to that of    the space becomes 1:1 (the smaller the value is, the higher the    sensitivity is).-   (ii) Resolution: expressed in terms of a minimum width of the lines    distinctly formed by exposing at the amount of exposed dose in which    the line width of the mask is 0.20 μm, the ratio of the width of the    line relative to that of the space becomes 1:1 (the smaller the    value is, the higher the resolution is).-   (iii) Oxygen plasma resistance: evaluated in the same manner as    Example 1.    The results are shown in Table 2.

TABLE 2 Composition Active Photosensitive component resin (silicasol)O₂-RIE (parts by (parts by Sensitivity Resolution rate weight) weight)(mJ/cm²) (μm) (nm/sec) Ex. 3 1 0.11 21 0.15 55 Ex. 4 1 0.25 15 0.14 25Comp. 1 0 30 0.19 90 Ex. 2

Examples 5 to 8 and Comparative Example 3

1. Preparation of a Photosensitive Resin Composition

(1) Preparation of Photosensitive Resin

Into 200 mL of toluene, were dissolved 30 g of tert-butyl methacrylateand 0.2 g of azobisisobutylonitrile. The reactor is substituted byargon, polymerization was conducted, by heating solution at 60° C. for12 hours with stirring. After completion of the polymerization, thereaction solution was poured into a large amount of methanol to solidifya resin, and the solidified resin was rinsed with methanol severaltimes. This resin was dried at room temperature, under a reducedpressure for one night to prepare a poly tert-butyl methacrylate havinga weight average molecular weight of 35000 at a yield of 33%.

Into 1 part by weight of this poly tert-butyl methacrylate, was added0.02 part by weight of the photoactive acid generator (B) used inExample 3, and mixed with 6 parts by weight of propylene glycolmonomethyl ether acetate as a solvent to prepare a positive photoresist.

(2) Active Component (Silicasol)

(i) Synthesis of a Silicasol

Into a 300 ml reactor, were fed 70 g of propylene glycol monomethyletheracetate (PGMEA) and 54 g of 20% by weight aqueous ammonia, and thereaction mixture was stirred at 30° C. for 20 minutes. Into theresultant solution, 26.3 g of tert-butyl3-[3-(triethoxysilyl)propylthio]propionate synthesized in the step(2)(ii) in Example 3, 7.8 g of tetraethoxysilane and 6.7 g oftriethoxymethylsilane were respectively added dropwise for 1 hour, andfurther stirred at 30° C. for 6 hours. Thereafter, the reaction solutionwas filtered by a membrane filter having mean hole size of 0.1 μm, andthen ammonia was removed by rinsing the filtrate with purified water,and further water was removed by dehydration under a reduced pressure.After that, the content of propylene glycol monomethylether acetate(PGMEA) was adjusted to prepare a propylene glycol monomethyletheracetate (PGMEA) solution of silicasol in which content of silicasol is30% by weight.

(3) Preparation of a Photosensitive Resin Composition

The photosensitive resin obtained in the step (1) and the activecomponent (silicasol) obtained in the step (2) were mixed together inthe ratio specified in Table 3 (denoted by solid ratio without solvent)to prepare a photosensitive resin composition. Incidentally, the examplewithout the active component (silicasol) was made as Comparative Example3.

2. Pattern Formation and Evaluation of Properties (Sensitivity,Resolution and Oxygen Plasma Resistance)

(1) Pattern Formation

After treating a washed silicon wafer by hexamethyldisilazane, thephotosensitive resin composition was coated on the wafer by means of aspin coater in order that a resist layer of 0.12 μm thick after driedwas formed, and the wafer was baked on a hot plate at 130° C. for 1minute. Thereafter, exposure was carried out using an exposing machine(manufactured by Litho Tech Japan Co. Ltd., VUVES-1200) having anexposing wavelength of 157 nm (F₂ excimer laser) with the exposureamount varied in steps. After baking the wafer at 130° C. on a hot platefor 1 minute, the wafer was paddle-developed with 2.38% by weight of atetramethylammonium hydroxide aqueous solution for 1 minute to give apositive pattern.

(2) Evaluation of the Properties

The positive pattern was evaluated for its properties according to thefollowing manner.

-   (i) Sensitivity: expressed in terms of the minimum amount of light    exposure in which a resist was completely dissolved (the smaller the    value is, the higher the sensitivity is).-   (ii) Resolution: plotting logarithm of dissolving rate (nm/sec)    relative to the amount of light exposure, finding slope angle θ of    the liner part, making the γ value of tan θ as index of resolution    (generally the larger the γ value is, the higher the resolution is).-   (iii) Oxygen plasma resistance: evaluated in the same manner as    Example 1.

The results are shown in Table 3.

TABLE 3 Composition Active Photosensitive component resin (silicasol)O₂-RIE (parts by (parts by Sensitivity Resolution rate weight) weight)(mJ/cm²) (γ value) (nm/sec) Ex. 5 1 0.11 5 3.8 93 Ex. 6 1 0.25 4 5.3 48Ex. 7 1 0.43 3 4.3 32 Ex. 8 1 1.00 1.5 3.0 20 Comp. 1 0 8 1.2 150 Ex. 3

Examples 9 to 12 and Comparative Example 4

1. Photosensitive Resin Composition

(1) Preparation of a Photosensitive Resin

To 1 part by weight of polyvinylphenol resin having a weight averagemolecular weight of 8,000 in which 35 mol % of the hydroxyl group wassubstituted with t-BOC (tert-butoxycarbonyloxy) group, was added 0.02part by weight of the photoactive acid generator represented by thefollowing formula (A), and to the resultant mixture, 6 parts by weightof propylene glycol monomethyl ether acetate as a solvent were added andmixed to prepare a positive photoresist.

(2) Active Component

(i) (ii) Synthesis of 1-(t-butoxycarbonyloxy)-4-iodobenzene and1-[2-{(3-trimethoxysilyl)propyloxycarbonyl}vinyl]-4-(t-butoxycarbonyloxy)benzene

In the same manner with the steps (i) and (ii) in Example 1,1-(t-butoxycarbonyloxy)-4-iodobenzene and1-[2-{(3-trimethoxysilyl)propyloxycarbonyl}vinyl]-4-(t-butoxycarbonyloxy)benzenewere synthesized.

(iii) Modification of Silicasol

0.45 g of1-[2-{(3-trimethoxysilyl)propyloxycarbonyl}vinyl]-4-(t-butoxycarbonyloxy)benzeneobtained by the step (ii) was mixed with 15 g of colloidal silica(manufactured by Nissan Chemical Industries, Ltd., NPC-ST, silicasolcontent: 30%by weight) and 0.23 g of 0.05 mol/L hydrochloric acid,stirred at room temperature for 16 hours to modify silicasol. In thisexample, a weight ratio of 3-(trimethoxysilyl)propylp-(t-butoxycarbonyloxy)cinnamate relative to silicasol is 1-10, andexpressed it as a modified amount of 10% (modified silicasol A).

Moreover, in the modifying step of the silicasol, modified silicasolswere prepared wherein the modified amount by 3-(trimethoxysilyl)propylp-(t-butoxycarbonyloxy)cinnamate is 15% (modified silicasol B) and 30%(modified silicasol C), respectively, in the same operation with theabove, except for the weight ratio of1-[2-{(3-trimethoxysilyl)propyloxycarbonyl}vinyl]-4-(t-butoxycarbonyloxy)benzene/colloidalsilica NPC-ST (solid basis)/hydrochloric acid (concentration of 0.05mol/L) is 1.5/10/0.75 and 3/10/1.5.

(3) Preparation of a Photosensitive Resin Composition

The photosensitive resin obtained in the step (1) and the modifiedsilicasol obtained in the step (2) were mixed together in the ratiospecified in Table 4 (denoted by solid ratio without solvent) to preparea photosensitive resin composition. Incidentally, the example withoutthe modified silicasol was made as Comparative Example 4.

2. Pattern Formation and Evaluation of Properties (Sensitivity,Resolution and Oxygen Plasma Resistance)

(1) Pattern Formation

The photosensitive resin composition was coated on a washed siliconwafer by means of a spin coater in order that a resist layer of 0.40 μmthick after dried was formed, and the wafer was baked on a hot plate at100° C. for 1 minute. Thereafter, exposure was carried out through atest mask having a line-and-space pattern with different line widths,using a reduced projection exposing machine (manufactured by Canon Inc.,FPA-3000EX5, NA=0.63) having an exposing wavelength of 248 nm with theexposure amount varied in steps. After baking the wafer at 100° C. on ahot plate for 1 minute, the wafer was paddle-developed with 2.38% byweight of a tetramethylammonium hydroxide aqueous solution for 1 minuteto give a positive pattern.

(2) Evaluation of the Properties

The positive pattern was evaluated for its properties according to thefollowing manner.

-   (i) sensitivity: evaluated in the same manner as Example 1.-   (ii) resolution: evaluated in the same manner as Example 1.-   (iii) heat resistance: the wafers after development were separately    placed on hot plates different in temperature for 5 minutes. The    temperatures at which the patterns with 500 μm width began to deform    were used as indexes of heat resistance.-   (iv) Oxygen plasma resistance: evaluated in the same manner as    Example 1.

The results are shown in Table 4.

TABLE 4 Composition Modified Modified Photosensitive colloidal amount ofresin silica colloidal Heat (parts by (parts by silica SensitivityResolution resistance O₂-RIE rate weight) weight) (%) (mJ/cm²) (μm) (°C.) (nm/sec) Ex. 9 1 A 10 25 0.17 120 41 0.11 Ex. 10 1 A 10 20 0.18 13011 0.25 Ex. 11 1 B 15 25 0.16 120 40 0.11 Ex. 12 1 C 30 28 0.15 120 420.11 Comp. Ex. 4 1 0 — 50 0.23 100 70

Example 13 and Comparative Examples 5 to 6

1. Preparation of a Photosensitive Resin Composition

(1) Preparation of a Photosensitive Resin

Into a reactor, were fed 30 g of t-butyl methacrylate and 0.2 g ofazobisisobutylonitrile, and dissolved to 200 mL of toluene. The reactoris substituted by argon, polymerization was conducted by heatingsolution at 60° C. with stirring for 12 hours. After completion of thepolymerization, the reaction solution was poured into a large amount ofmethanol to solidify a resin. The solidified resin was rinsed withmethanol several times. Thus obtained resin was dried at roomtemperature, under a reduced pressure for one night to prepare a polytert-butyl methacrylate having a weight average molecular weight of35000 (33% yield).

Into 1 part by weight of thus obtained poly tert-butyl methacrylateresin, was added 0.02 part by weight of the photoactive acid generatorrepresented by the following formula (B), and mixed with 6 parts byweight of propylene glycol monomethyl ether acetate as a solvent toprepare a positive photoresist.

(2) Active Component

(i) Synthesis of tert-butyl 3-[3-(triethoxysilyl)propiothio]Propionate

tert-Butyl 3-[3-(triethoxysilyl)propiothio]propionate was synthesized inthe same manner as the step (i) in Example 3.

(ii) Modification of Silicasol

0.45 g of tert-butyl 3-[3-(triethoxysilyl)propiothio] propionatesynthesized by the step (i) was mixed with 15 g of colloidal silica(manufactured by Nissan Chemical Industries, Ltd., NPC-ST, silicasolcontent: 30% by weight) and 0.23 g of 0.05 mol/L hydrochloric acid, andstirred at room temperature for 16 hours to modify silicasol. In thisexample, the modified amount was 10% (modified silicasol D).

(3) Preparation of a Photosensitive Resin Composition

The photosensitive resin obtained in the step (1) and the modifiedsilicasol D obtained in the step (2) were mixed together in the ratiospecified in Table 5 (denoted by solid ratio without solvent) to preparea photosensitive resin composition. Incidentally, the example usingunmodified silicasol [manufactured by Nissan Chemical Industries, Ltd.,colloidal silica NPC-ST, silicasol content: 30% by weight] instead ofthe modified silica D was made as Comparative Example 5, and the examplewithout the silicasol was made as Comparative Example 6.

2. Pattern Formation and Evaluation of Properties (Sensitivity,Resolution, Heat Resistance and Oxygen Plasma Resistance)

(1) Pattern Formation

The photosensitive resin composition was coated on a washed siliconwafer by means of a spin coater in order that a resist layer of 0.30 μmthick after dried was formed, and the wafer was baked on a hot plate at130° C. for 1 minute. Thereafter, exposure was carried out through atest mask having a line-and-space pattern with different line widths,using a reduced projection exposing machine (NA=0.60) having an exposingwavelength of 193 nm with the exposure amount varied in steps. Afterbaking the wafer at 130° C. on a hot plate for 1 minute, the wafer waspaddle-developed with 2.38% by weight of a tetramethylammonium hydroxideaqueous solution for 1 minute to give a positive pattern.

(2) Evaluation of the Properties

The positive pattern was evaluated for its properties according to thefollowing manner.

(i) sensitivity, (ii) resolution and (iii) oxygen plasma resistance:evaluated in the same manner as Example 3. The results are shown inTable 5.

TABLE 5 Composition Modified Modified Photosensitive colloidal amount ofresin silica colloidal (parts by (parts by silica Sensitivity ResolutionO₂-RIE rate weight) weight) (%) (mJ/cm²) (μm) (nm/sec) Ex. 13 1 modified10 7 0.14 68 silicasol D 0.11 Comp. Ex. 5 1 un- 0 7 0.18 72 modifiedsilicasol 0.11 Comp. Ex. 6 1 0 — 14 0.18 150

Examples 14 to 16 and Comparative Examples 7 to 8

1. Preparation of a Photosensitive Resin Composition

The photosensitive resin (1) used in Example 9 or the photosensitiveresin (2) used in Example 13, and a modified silicasol were mixedtogether in the ratio specified in Table 6 (denoted by solid ratiowithout solvent) to prepare a photosensitive resin composition.

Incidentally, regarding Example 15, in the modification step ofsilicasol in Example 9, a modified silicasol of 100% modification amount(modified silicasol E) was used, which was obtained by the same manneras Example 9 except that the weight ratio of1-[2-{(3-trimethoxysilyl)propyloxycarbonyl}vinyl]-4-(t-butoxycarbonyloxy)benzene/colloidalsilica NPC-ST (solid basis)/hydrochloric acid (concentration of 0.5mol/L) was used as 10/10/5.

2. Pattern Formation and Evaluation of Properties (Sensitivity,Resolution, Heat Resistance and Oxygen Plasma Resistance)

(1) Pattern Formation

The photosensitive resin composition was coated on a washed wafer bymeans of a spin coater in order that a resist layer of 0.12 μm thickafter dried was formed, and the wafer was baked on a hot plate at thetemperature shown in Table 6 for 1 minute. Thereafter, exposure wascarried out through a test mask having a line-and-space pattern withdifferent line widths, using an exposing machine (manufactured by LithoTech Japan Co. Ltd., VUVES-4500) having a F₂ excimer laser (exposingwavelength: 157 nm) as an exposure light source with the exposure amountvaried in steps. After baking the wafer at the temperature shown inTable 6 on a hot plate for 1 minute, the wafer was paddle-developed with2.38% by weight of a tetramethylammonium hydroxide aqueous solution for1 minute to give a positive pattern.

(2) Evaluation of the Properties

Regarding the positive pattern, (i) sensitivity was expressed as thelight exposure in which film thickness of the exposed area becomes 0,(the smaller the value is, the higher the sensitivity is), (ii)resolution was evaluated with the following process, making asensitivity curve plotting of the thickness of a residual resist layerin the exposed area, relative to logarithm of an amount of lightexposure, and finding a slope of the linear part (γ value) at the pointof film thickness being 0 to treat it as index of resolution (the largerthe value is, the higher the resolution is). Moreover, (iii) oxygenplasma resistance: evaluated in the same manner as Example 1.

The results are shown in Table 6.

TABLE 6 Composition Modified Modified Photosensitive colloidal amount ofBaking resin silica colloidal after (parts by (parts by silica Prebaking exposure Sensitivity O₂-RIE rate weight) weight) (%) (° C.) (°C.) (mJ/cm²) γ value (nm/sec) Ex. 14 resin(1) A 10 100 100 16 3.7 39 10.11 Ex. 15 resin(1) E 100 100 100 12 4.5 37 1 0.11 Comp. resin(1) 0 —100 100 35 1.2 70 Ex. 7 1 Ex. 16 resin(2) D 10 130 130 9 4.2 20 1 0.25Comp. resin(2) 0 — 130 130 15 1.5 150 Ex. 8 1

Examples 17 to 20 and Comparative Examples 9 to 11

1. Preparation of a Photosensitive Resin Composition

(1) Photosensitive Resin

To 1 part by weight of polyvinylphenol resin having a weight averagemolecular weight of 8,500 in which 45 mol % of the hydroxyl group wassubstituted with ethoxyethyl group, was added 0.03 part by weight of thephotoactive acid generator represented by the above-mentioned formula(A), and to the resultant mixture, 6 parts by weight of propylene glycolmonomethyl ether acetate as a solvent were added and mixed to prepare apositive photoresist.

(2) Active Component

(i) Synthesis of 1-(t-butoxycarbonyoxy)-4-bromobenzene

Into 200 ml of acetone, in which 25.0 g (144.5 mmol) of p-bromophenoland 17.7 mg (0.14 mmol) of N,N-dimethylaminopyridine were dissolved,31.5 g (144.5 mmol) of di-t-butylcarbonate was added dropwise at 40° C.After dropping, the reaction was kept with stirring for one night. Aftercompletion of the reaction, the reaction solution was put into 1 L oficed water. The formed precipitation was collected by suctionfiltration, dried and recrystallized by methanol to prepare 22.6 g of1-(t-butoxycarbonyloxy)-4-bromobenzene.

(ii) Synthesis of1-(2-trimethoxysilylvinyl)-4-(t-butoxycarbonyloxy)benzene

Into a mixture of 20 ml of triethylamine and 40 ml of acetonitrile, weredissolved 15.0 g (54.9 mmol) of 1-(t-butoxycarbonyloxy)-4-bromobenzenesynthesized in the step (i) and 9.76 g (65.9 mmol) ofvinyltrimethoxysilane, and the reaction system was substituted by argonby bubbling argon in thus obtained solution. In the reaction system, wasadded 246.5 mg (1.1 mmol) of palladium acetate as a catalyst, themixture was refluxed for one night. After completion of the reaction,solvent was removed, and the obtained residue was extracted by hexane.Hexane was removed from the extraction to prepare 9.5 g of1-(2-trimethoxysilylvinyl)-4-(t-butoxycarbonyloxy)benzene being theobjective compound.

The formula of the above-mentioned reaction steps is shown as follows:

The ¹H-NMR spectrum of the obtained compound is shown in FIG. 5.

¹H-NMR(CDCl₃) ppm: 1.6(s, 9H, t-Bu), 3.6(s, 9H, OCH₃), 6.1(d, 1H, C═CH),7.2(d, 2H, C₆H₄), 7.3(d, 1H, C═CH), 7.5(d, 2H, C₆H₄)

(ii) Modification of Silicasol

1-(2-Trimethoxysilylvinyl)-4-(t-butoxycarbonyloxy)benzene obtained inthe step (ii) was mixed with colloidal silica (manufactured by NissanChemical Industries, Ltd., NPC-ST, silicasol content: 30% by weight) and0.05 mol/L hydrochloric acid, in a weight ratio of1-(2-trimethoxysilylvinyl)-4-(t-butoxycarbonyloxy)benzene/colloidalsilica NPC-ST (without solvent)/hydrochloric acid being 5/10/2.5(modified amount of 50%) and 10/10/5 (modified amount of 100%), themixture was stirred at room temperature for 16 hours to modify silicasol(the former is named as modified silicasol F, the latter, silicasol G).

(3) Preparation of a Photosensitive Resin Composition

The photosensitive resin obtained in the step (1) and the modifiedsilicasol obtained in the step (2) were mixed together in the ratioshown in Table 7 (denoted by solid ratio without solvent) to prepare aphotosensitive resin composition. Incidentally, the examples using theunmodified silicasol instead of the modified silicasol were made asComparative Example 9 and 10, and the example without the silicasol wasmade as Comparative Example 11.

2. Pattern Formation and Evaluation of the Properties (Sensitivity,Resolution and Oxygen Plasma Resistance)

Conducted in the same way as Example 9.

TABLE 7 Composition Modified Modified colloidal amount of Photosensitivesilica colloidal resin (parts (parts by silica Sensitivity ResolutionO₂-RIE rate by weight) weight) (%) (mJ/cm²) (μm) (nm/sec) Ex. 17 1modified 50 28 0.16 33 silicasol F 0.11 Ex. 18 1 modified 50 20 0.15 8silicasol F 0.25 Ex. 19 1 modified 100 30 0.15 32 silicasol G 0.11 Ex.20 1 modified 100 19 0.14 8 silicasol G 0.25 Comp. Ex. 1 un- 0 28 0.2135 9 modified silicasol 0.11 Comp. Ex. 1 un- 0 21 0.23 10 10 modifiedsilicasol 0.25 Comp. Ex. 1 0 — 40 0.21 75 11

Examples 21 to 23 and Comparative Example 12

1. Preparation of a Photosensitive Resin Composition

(1) Photosensitive Resin

To 1 part by weight of polyvinylphenol resin having a weight averagemolecular weight of 9,300 in which 40 mol % of the hydroxyl group wassubstituted with ethoxyethyl group, was added 0.02 part by weight of thephotoactive acid generator represented by the above-mentioned formula(A), and to the resultant mixture, 6 parts by weight of propylene glycolmonomethyl ether acetate as a solvent were added and mixed to prepare apositive photoresist.

(2) Active Component

(i) Synthesis of 1-benzyloxy-4-t-butoxycarbonyoxybenzene

Into 200 ml of acetone, were dissolved 25.0 g (124.9 mmol) of4-benzyloxyphenol and 15.3 mg (0.12 mmol) of N,N-dimethylaminopyridine,and 27.2 g (124.9 mmol) of di-t-butylcarbonate was added dropwise at 40°C. After completion of dropping, the reaction was kept with stirring forone night. After completion of the reaction, the reaction solution wasput into 1 L of iced water. The formed precipitation was collected bysuction filtration, dried, and recrystallized by methanol to prepare22.8 g of 1-benzyloxy-4-t-butoxycarbonyoxybenzene.

(ii) Synthesis of 4-t-butoxycarbonyoxyphenol

Into 20.0 g (66.6 mmol) of 1-benzyloxy-4-t-butoxycarbonyoxybenzenesynthesized in the step (i), were fed 150 ml of ethanol and 0.5 g of10%-palladium carbon powder, and the mixture was reacted with 1492.2 ml(66.6 mmol) of hydrogen at room temperature with stirring. The reactionsolution was filtrated to remove palladium carbon powder, and thefiltrate was concentrated. After redissolving the concentrated filtrateto toluene, the solution was filtrated to remove insoluble. And then,the solution was kept still, and recrystallized to prepare4-t-butoxycarbonyoxyphenol.

(iii) Reaction of 4-t-butoxycarbonyoxyphenol with Silane Coupling Agent

Into 8.4 g (40.0 mmol) of 4-t-butoxycarbonyoxyphenol synthesized in thestep (ii), were fed 20 ml of n-hexane dehydrated sufficiently, and 9.9 g(40.0 mmol) of 3-isocyanatopropyltriethoxysilane, and the mixture wasallowed to react at room temperature for 16 hours with stirring.

The reaction solution was filtrated, and the filtrate was redissolved to200 ml of a mixture of hexane and toluene in a weight ratio of 1/1, andthen thus obtained solution was filtrated, and the resultant filtratewas recrystallized to give a product.

The formula of the above-mentioned reaction steps is shown as follows:

The ¹H-NMR spectrum of the obtained product is shown in FIG. 6.

¹H-NMR(CDCl₃) ppm: 0.7(t, 2H, CH₂), 1.2(t, 9H, OCH₂CH₃), 1.6(s, 9H,t-Bu), 1.7(t, 2H, CH₂), 3.3(t, 2H, CH₂), 3.9(q, 6H, CH₂), 5.4(t, 1H,NH), 7.2(d, 4H, C₆H₄)

(iv) Modification of Silicasol

The compound synthesized in the step (iii) was mixed with colloidalsilica (manufactured by Nissan Chemical Industries, Ltd., NPC-ST,silicasol content: 30% by weight) and 0.05 mol/L hydrochloric acid, in aweight ratio of the compound synthesized in the step (iii)/colloidalsilica NPC-ST (without solvent)/hydrochloric acid being 5/10/2.5(modified amount of 50%) and 10/10/5 (modified amount of 100%), themixture was stirred at room temperature for 16 hours to modify silicasol(the former is mentioned as modified silicasol H, the latter ismentioned as modified silicasol I).

(3) Preparation of a Photosensitive Resin Composition

The photosensitive resin obtained in the step (1) and the modifiedsilicasol obtained in the step (2) were mixed together in the ratiospecified in Table 8 (denoted by solid ratio without solvent) to preparea photosensitive resin composition. Incidentally, the example withoutthe modified silicasol was made as Comparative Example 12.

2. Pattern Formation and Evaluation of the Properties (Sensitivity,Resolution and Oxygen Plasma Resistance)

Conducted in the same way as Example 9.

TABLE 8 Composition Modified Modified colloidal amount of Photosensitivesilica colloidal resin (parts (parts by silica Sensitivity ResolutionO₂-RIE rate by weight) weight) (%) (mJ/cm²) (μm) (nm/sec) Ex. 21 1modified 50 12 0.14 2 silicasol H 0.43 Ex. 22 1 modified 100 22 0.14 9silicasol I 0.25 Ex. 23 1 modified 100 11 0.13 3 silicasol I 0.43 Comp.Ex. 1 0 — 32 0.22 80 12

Example 24

(i) Synthesis of 1-(1-ethoxy)ethoxy-4-bromobenzene

Into 100 ml of dehydrated ethyl acetate, were fed 11.0 g (50 mmol) ofp-bromophenol, and 4.8 ml of a solution composed of hydrochloric acid(1.0 mol/L) and ether, and the mixture was set at 40° C. Into themixture, 10.8 g (150 mmol) of ethylvinylether was added dropwise, andthe mixture was kept with stirring for one night. After completion ofthe reaction, the reaction solution was rinsed with sodium hydrogencarbonate solution and then rinsed with water to remove solvent. Bypurifying with silica gel column chromatography (eluate: hexane), 10.7 g(36.5 mmol) of 1-(1-ethoxy)ethoxy-4-bromobenzene was obtained.

NMR(CDCl₃) ppm: 1.2(t, 3H, terminal CH₃), 1.49 (t, 3H, branched CH₃),3.47 to 3.6(m, 1H, OCH), 3.7 to 3.85(m, 1H, OCH), 5.34(q, 1H, branchedOCH), 6.9(d, 2H, C₆H₄), 7.38(d, 2H, C₆H₄)

(ii) Synthesis of4-[2-{(3-trimethoxysilyl)propyloxycarbony}vinyl]-1-{(1-ethoxy)ethoxy}benzene

The objective compound was obtained in the same way with Hech reactionin the step (2) (ii) of Example 1, except for using1-(1-ethoxy)ethoxy-4-bromobenzene synthesized in the step (i) instead of1-(t-butoxycarbonyloxy)-4-iodobenzene in the step (2) (ii) in Example 1.

NMR(CDCl₃) ppm: 0.7(t, 2H, CH₂), 1.2(t, 3H, terminal CH₃), 1.49(t, 3H,branched CH₃), 1.8(t, 2H, CH₂), 3.55 to 3.65(m, 9H, OCH₃), 3.47 to3.6(m, 1H, OCH), 3.7 to 3.85(m, 1H, OCH), 4.2(t, 2H, CH₂), 5.34(q, 1H,branched OCH), 6.4(d, 1H, C═CH), 7.6(d, 1H, C═CH), 6.9(d, 2H, C₆H₄),7.38(d, 2H, C₆H₄)

Example 25

(i) Synthesis of 1-(1-ethoxy)ethoxy-4-bromobenzene

The objective compound was obtained in the same manner as the step (i)in Example 24.

(ii) Synthesis of 4-[2-(trimethoxysilyl)vinyl]-1-(1-ethoxy)ethoxybenzene

The objective compound was obtained in the same manner as Hech reactionin the step (2) (ii) of Example 1, except for using1-(1-ethoxy)ethoxy-4-bromobenzene and trimethoxyvinylsilane instead of1-(t-butoxycarbonyloxy)-4-iodobenzene and 3-trimethoxysilylpropylesterof acrylic acid.

NMR(CDCl₃) ppm: 1.2(t, 3H, terminal CH₃), 1.49(t, 3H, branched CH₃),3.47 to 3.6(m, 1H, OCH), 3.6(m, 9H, OCH₃), 3.7 to 3.85(m, 1H, OCH),5.34(q, 1H, branched OCH), 6.1(d, 1H, C═CH), 7.18(d, 2H, C₆H₄), 7.25(d,1H, C═CH), 7.5(d, 2H, C₆H₄)

Example 26

(i) Synthesis of 1-benzyloxy-3-acetoxybenzene

Into 300 ml of dimethylsulfoxide, 30.4 g (200 mmol) ofresorcylmonoacetate was dissolved, and aqueous solution of sodiumhydrate (NaOH/H₂O: 8 g/30 ml) was added to this solution and stirreduntil the mixture being uniform. Then, 26.5 g (210 mmol) of benzylchloride was added into the mixture, and allowed to react at roomtemperature for 24 hours. The reaction mixture was put into 1 L of icedwater, and the obtained solid was collected by filtration, dried andrecrystallized by ethanol to prepare 44.3 g (183 mmol) of1-benzyloxy-3-acetoxybenzene.

(ii) Synthesis of 3-benzyloxyphenol

In 300 ml of 10% water-containing ethanol, 20 g (82 mmol) of1-benzyloxy-3-acetoxybenzene obtained in the step (i) was hydrolyzedwith 16.3 g (248 mmol) of potassium hydroxide, and neutralized toprepare 14.8 g (74 mmol) of 3-benzyloxyphenol.

(iii) Synthesis of 1-(1-ethoxy)ethoxy-3-benzyloxybenzene

The objective compound was obtained in the same way with the step (i) ofExample 24, except for using 3-benzyloxyphenol instead of p-iodophenol.

(iv) Synthesis of 3-(1-ethoxy)ethoxyphenol

The objective compound was obtained in the same way with the step (2)(ii) of Example 21, except for using1-(1-ethoxy)ethoxy-3-benzyloxybenzene obtained in the step (iii) insteadof 1-benzyloxy-4-t-butoxycarbonyloxybenzene in the step (2) (ii) inExample 21.

(v) Synthesis of1-(1-ethoxy)ethoxy-3-[(3-triethoxysilyl)propylaminocarbonyloxy]benzene

The objective compound was obtained in the same way with the step (2)(iii) of Example 21, except for using 3-(1-ethoxy)ethoxyphenol obtainedin the step (iv) instead of 4-t-butoxycarbonyloxyphenol.

The formula of the above-mentioned reaction steps is shown as follows:

Example 27

(i) Synthesis of 1-benzyloxy-3-t-butoxycarbonyloxybenzene

The objective compound was obtained in the same way with the step (2)(i) of Example 21, except for using 3-benzyloxyphenol instead of4-benzyloxyphenol in the step (2) (i) in Example 21.

(ii) Synthesis of 3-t-butoxycarbonyloxyphenol

The objective compound was obtained in the same way with the step (2)(ii) of Example 21, except for using1-benzyloxy-3-t-butoxycarbonyloxybenzene obtained in the step (i)instead of 1-benzyloxy-4-t-butoxycarbonyloxybenzene in the step (2) (ii)in Example 21.

(iii) Reaction of 3-t-butoxycarbonyloxyphenol with Silane Coupling Agent

1-[3-(Triethoxysilyl)propylaminocarbonyloxy]-3-[t-butoxycarbonyloxy]benzenewas obtained in the same way with the step (2) (iii) of Example 21,except for using 3-t-butoxycarbonyloxyphenol obtained in the step (ii)instead of 4-t-butoxycarbonyloxyphenol in the step (2) (iii) in Example21.

The formula of the above-mentioned reaction steps is shown as follows:

Example 28 Synthesis of 2-(triethoxysilyl)-1-(t-butoxycarbonyl)ethane

Into the 100 ml of dried tetrahydrofuran, were fed 25.8 g (20 mmol) oft-butyl acrylate and 32.8 g (20 mmol) of triethoxysilane, and themixture was substituted by argon. To the mixture solution, 10 mg ofchloroplatinic acid was added and the mixture was heated for 24 hoursunder reflux. After completion of the reaction, 58.5 g of the objectivecompound was obtained by removing solvent.

Example 29 Synthesis ofN-[2-(t-butoxycarbonyl)ethyl]-3-(triethoxysilyl)propylamine

In dehydrated ethanol, 22.1 g (100 mmol) of 3-aminopropyltriethoxysilanewas dissolved, and to the solution, was added 12.8 g (100 mmol) oft-butyl acrylate, and the mixture was stirred at room temperature for 24hours. After completion of the reaction, 32.5 g of the objectivecompound was obtained by removing solvent.

NMR(CDCl₃) ppm: 0.6(t, 2H, CH₂), 1.19(t, 9H, CH₃), 1.41(s, 9H, t-Bu),1.49 to 1.67(m, 2H, CH₂), 2.4(t, 2H, CH₂), 2.59(t, 2H, CH₂), 2.8(t, 2H,CH₂), 3.79(q, 6H, OCH₂)

The above-mentioned reaction formula is shown as follows:

Example 30 Synthesis ofN,N′-di-(t-butoxycarbonyl)ethyl-3-(triethoxysilyl)propylamine

The objective compound was obtained in the same way with Example 29,except for using 25.6 g (200 mmol) of t-butylester of acrylic acid andheating for 24 hours under reflux.

NMR(CDCl₃) ppm: 0.5(t, 2H, CH₂), 1.19(t, 9H, CH₃), 1.39(s, 18H, t-Bu),1.41 to 1.6(m, 2H, CH₂), 2.3(t, 6H, CH₂), 2.7(t, 4H, CH₂), 3.75(q, 6H,OCH₂)

The above-mentioned reaction formula is shown as follows:

Then, the properties of pattern were evaluated in the same manner asExample 2, except for using the compounds (active components) obtainedin Examples 24 to 30 instead of the active component used in Example 2.The results of Examples 24 to 30 were same as the results of Example 2.

1. An active component for use in combination with a photosensitizer comprising a photosensitive resin composition, wherein the active component comprises at least one member selected from the group consisting of (a) an active metal alkoxide represented by the following formula (1): (X)_(m-n)-M^(m)-[(U₁)_(p)—(U₂-Z)_(t)]_(n)  (1) wherein, X represents a hydrogen atom, a halogen atom, an alkoxy group or an alkoxycarbonyl group, M represents a metal atom whose valence m is not less than 2, U₁ represents a first connecting unit, U₂ represents a second connecting unit, Z represents a group causing a difference in solubility by light exposure, n represents an integer of not less than 1 with m>n, p represents 0 or 1, and t represents an integer of not less than 1, wherein the unit (U₁)_(p)—(U₂-Z)_(t) in the formula (1) is represented by the following formula (3): [(R¹)_(q)—(B)_(r)]_(p)—[{(R²)_(u)—(Ar)_(v)}-Z]_(t)  (3) wherein R¹ and R², is either the same or different, representing an alkylene group or an alkenylene group, B represents an ester bond, a thioester bond, an amide bond, a urea bond, a urethane bond, a thiourethane bond, an imino group, a sulfur atom or a nitrogen atom, Ar represents an arylene group or a cycloalkylene group, r and p are each 1; q, u, and v are each either 0 or 1; and q+r+u+v≧1, and t has the same meanings defined above; or a polycondensate thereof, and (b) a particle represented by the following formula (2): P—[(Y)_(s)-{(U₁)_(p)—(U₂-Z)_(t)}]_(k)  (2) wherein P represents a fine particle carrier, Y represents a coupling residue, k represents an integer of not less than 1, s represents 0 or 1, and U₁, U₂, Z, p and t have the same meanings defined above.
 2. An active component according to claim 1, which is in the form of a particle, or an oligomer.
 3. An active component according to claim 1, wherein the group Z is (a) a photo-crosslinkable group or a photo-curable group, or (b) a hydrophilic group protected by a protective group which is capable of being removed by light exposure.
 4. An active component according to claim 1, wherein the group Z is a hydrophilic group protected by a protective group which is capable of being removed by light exposure in association with a photosensitizer.
 5. An active component according to claim 3, wherein the protective group is capable of being removed by an acid.
 6. An active component according to claim 1, wherein the group Z is capable of forming a hydroxyl group or a carboxyl group by removal of a hydrophobic protective group.
 7. An active component according to claim 3, wherein the protective group is (i) a protective group for a hydroxyl group, selected from the group consisting of an alkoxyalkyl group, an acyl group, an alkoxycarbonyl group, an oxacycloalkyl group and a crosslinked cyclic alicyclic group; or (ii) a protective group for a carboxyl group, selected from the group consisting of an alkyl group, a carbamoyl group and a crosslinked cyclic or alicyclic group.
 8. An active component according to claim 3, wherein the protective group is (1) a protective group for a hydroxyl group, selected from the consisting of a C₁₋₆alkyl-carbonyl group, a C₁₋₆alkoxy-C₁₋₆alkyl group, a C₁₋₆alkoxy-carbonyl group and an oxacycloalkyl group; or (2) a protective group for a carboxyl group, selected from the group consisting of a C₁₋₆alkyl group, a carbamoyl group, a C₁₋₆alkyl-carbamoyl group, a C₆₋₁₀aryl-carbamoyl group and a bi- or tricycloalkyl group.
 9. An active component according to claim 1, wherein the metal atom M is one member selected from the group consisting of aluminium, titanium, zirconium and silicon.
 10. An active component according to claim 1, wherein the metal atom M is silicon.
 11. An active component according to claim 1, wherein each of the connecting units, U₁ and U₂, is a unit containing at least one member selected from the group consisting of a chain hydrocarbon, a hydrocarbon ring, a chain hydrocarbon having a hetero atom, and a heterocycle.
 12. An active component according to claim 1, wherein, in the formula (1), the group Z represents a hydroxyl or carboxyl group protected by a hydrophobic protective group which is capable of being removed by light exposure, and the metal atom M is selected from the group consisting of aluminium, titanium, zirconium and silicon.
 13. An active component according to claim 1, wherein the active metal alkoxide component is the polycondensate of the active metal alkoxide and the active component further comprises a metal alkoxide represented by the following formula (5): (X)_(m-n-1)(R⁵)_(n-1)  (5) wherein, R⁵ represents a hydrogen atom or an alkyl group, and X, M, m and n have the same meanings defined above.
 14. An active component according to claim 13, wherein the weight ratio of the polycondensate of the active metal alkoxide to the metal alkoxide ranges from 10/90 to 90/10.
 15. An active component according to claim 1, wherein the polycondensate is in the form of a particle having a mean particle size of 1 to 100 nm.
 16. An active component according to claim 1, wherein the mean particle size of the fine particle carrier ranges from 1 to 100 nm.
 17. An active component according to claim 1, wherein the fine particle carrier comprises an inorganic fine particle carrier.
 18. An active component according to claim 1, wherein the fine particle carrier comprises a silicasol.
 19. An active component comprising a particle, wherein the particle comprises a connecting unit U connecting with an inorganic fine particle P whose mean particle size is 1 to 50 nm through a silane coupling agent Y, a hydrophilic group connecting with the connecting unit, and a protective group which protects the hydrophilic group, wherein the hydrophilic group and the protective group constitute a group Z which causes a difference in solubility by light exposure; the connecting unit comprises at least one member selected from the group consisting an aromatic C₆₋₁₂hydrocarbon ring, a monocyclic alicyclic hydrocarbon ring, a crosslinked cyclic alicyclic hydrocarbon ring and an aliphatic hydrocarbon chain; the hydrophilic group is a hydroxyl group or a carboxyl group; and the protective group is (1) a protective group for the hydroxyl group, selected from the group consisting of a C₁₋₄ alkyl-carbonyl group, a C₁₋₄alkoxy-C₁₋₄alkyl group, a C₁₋₄alkoxy-carbonyl group and a 5- or 6-membered oxacycloalkyl group, or (2) a protective group for the carboxyl group, selected from the group consisting of a C₁₋₄alkyl group, a carbamoyl group, a C₁₋₄alkyl-carbamoyl group, a C₆₋₁₀aryl-carbamoyl group and a bi- or tricycloalkyl group.
 20. An active component according to claim 19, wherein the amount of the silane coupling agent is 0.1 to 200 parts by weight relative to 100 parts by weight of the fine particle carrier.
 21. A photosensitive resin composition which comprises a base resin, a photosensitizer and the active component according to claim
 1. 22. A photosensitive resin composition according to claim 21, wherein the resin composition is a positive and contains an exposed area that is water- or alkali-soluble.
 23. A photosensitive resin composition according to claim 21, wherein the base resin comprises a homo- or copolymer of a monomer which is capable of forming a hydrophilic group by reacting with an acid, and the photosensitizer comprises an photoactive acid generator.
 24. A process for forming a pattern, which comprises the steps of: applying or coating the photosensitive resin composition according to claim 21 onto a substrate, exposing the coating layer to light, heat-treating the light-exposed layer, and developing the heat-treated layer to form a pattern.
 25. An active metal alkoxide which is represented by the following formula (1): (X)_(m-n)-M^(m)-{(U₁)_(p)—(U₂-Z)_(t)]_(n)  (1) wherein X represents a hydrogen atom, a halogen atom, an alkoxy group or an alkoxycarbonyl group, M represents a metal atom whose valence m is not less than 2, U₁ represents a first connecting unit, U₂ represents a second connecting unit, Z represents a group causing a difference in solubility by light exposure, n represents an integer of not less than 1 with m>n, p represents 0 or 1, and t represents 1 or 2 wherein the unit (U₁)_(p)—(U₂-Z)_(t) in the formula (1) is represented by the following formula (3): [(R¹)_(q)—(B)_(r)]_(p)—[{(R²)_(u)—(Ar)_(v)}-Z]_(t)  (3) wherein R¹ and R², is either the same or different, representing an alkylene group or a alkenylene group, B represents an ester bond, a thioester bond, an amide bond, a urea bond, a urethane bond, a thiourethane bond, an imino group, a sulfur atom or a nitrogen atom, Ar represents an arylene group or a cycloalkylene group, r and p are each 1, q, u, and v are each either 0 or 1; and q+r+u+v≧1, and t has the same meaning defined above.
 26. An oligomer or an active particle, which comprises at least a polycondensate of an active metal alkoxide recited in claim
 25. 